Mybatis常用分頁(yè)插件實(shí)現(xiàn)快速分頁(yè)處理技巧
在未分享整個(gè)查詢(xún)分頁(yè)的執(zhí)行代碼之前,先了解一下執(zhí)行流程。
1.總體上是利用mybatis的插件攔截器,在sql執(zhí)行之前攔截,為查詢(xún)語(yǔ)句加上limit X X
2.用一個(gè)Page對(duì)象,貫穿整個(gè)執(zhí)行流程,這個(gè)Page對(duì)象需要用Java編寫(xiě)前端分頁(yè)組件
3.用一套比較完整的三層entity,dao,service支持這個(gè)分頁(yè)架構(gòu)
4.這個(gè)分頁(yè)用到的一些輔助類(lèi)
注:分享的內(nèi)容較多,這邊的話我就不把需要的jar一一列舉,大家使用這個(gè)分頁(yè)功能的時(shí)候缺少什么就去晚上找什么jar包即可,盡可能用maven包導(dǎo)入因?yàn)閙aven能減少版本沖突等比較好的優(yōu)勢(shì)。
我只能說(shuō)盡可能讓大家快速使用這個(gè)比較好用的分頁(yè)功能,如果講得不明白,歡迎加我QQ一起探討1063150576,。莫噴哈!還有就是文章篇幅可能會(huì)比較大,不過(guò)花點(diǎn)時(shí)間,把它看完并實(shí)踐一下一定會(huì)收獲良多。
第一步:既然主題是圍繞怎么進(jìn)行分頁(yè)的,我們就從mybatis入手,首先,我們把mybatis相關(guān)的兩個(gè)比較重要的配置文件拿出來(lái)做簡(jiǎn)要的理解,一個(gè)是mybatis-config.xml,另外一個(gè)是實(shí)體所對(duì)應(yīng)的mapper配置文件,我會(huì)在配置文件上寫(xiě)好注釋?zhuān)蠹乙豢淳蜁?huì)明白。
mybatis-config.xml
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!-- 全局參數(shù) --> <settings> <!-- 使全局的映射器啟用或禁用緩存。 --> <setting name="cacheEnabled" value="false"/> <!-- 全局啟用或禁用延遲加載。當(dāng)禁用時(shí),所有關(guān)聯(lián)對(duì)象都會(huì)即時(shí)加載。 --> <setting name="lazyLoadingEnabled" value="true"/> <!-- 當(dāng)啟用時(shí),有延遲加載屬性的對(duì)象在被調(diào)用時(shí)將會(huì)完全加載任意屬性。否則,每種屬性將會(huì)按需要加載。 --> <setting name="aggressiveLazyLoading" value="true"/> <!-- 是否允許單條sql 返回多個(gè)數(shù)據(jù)集 (取決于驅(qū)動(dòng)的兼容性) default:true --> <setting name="multipleResultSetsEnabled" value="true"/> <!-- 是否可以使用列的別名 (取決于驅(qū)動(dòng)的兼容性) default:true --> <setting name="useColumnLabel" value="true"/> <!-- 允許JDBC 生成主鍵。需要驅(qū)動(dòng)器支持。如果設(shè)為了true,這個(gè)設(shè)置將強(qiáng)制使用被生成的主鍵,有一些驅(qū)動(dòng)器不兼容不過(guò)仍然可以執(zhí)行。 default:false --> <setting name="useGeneratedKeys" value="false"/> <!-- 指定 MyBatis 如何自動(dòng)映射 數(shù)據(jù)基表的列 NONE:不隱射 PARTIAL:部分 FULL:全部 --> <setting name="autoMappingBehavior" value="PARTIAL"/> <!-- 這是默認(rèn)的執(zhí)行類(lèi)型 (SIMPLE: 簡(jiǎn)單; REUSE: 執(zhí)行器可能重復(fù)使用prepared statements語(yǔ)句;BATCH: 執(zhí)行器可以重復(fù)執(zhí)行語(yǔ)句和批量更新) --> <setting name="defaultExecutorType" value="SIMPLE"/> <!-- 使用駝峰命名法轉(zhuǎn)換字段。 --> <setting name="mapUnderscoreToCamelCase" value="true"/> <!-- 設(shè)置本地緩存范圍 session:就會(huì)有數(shù)據(jù)的共享 statement:語(yǔ)句范圍 (這樣就不會(huì)有數(shù)據(jù)的共享 ) defalut:session --> <setting name="localCacheScope" value="SESSION"/> <!-- 設(shè)置但JDBC類(lèi)型為空時(shí),某些驅(qū)動(dòng)程序 要指定值,default:OTHER,插入空值時(shí)不需要指定類(lèi)型 --> <setting name="jdbcTypeForNull" value="NULL"/> <setting name="logPrefix" value="dao."/> </settings> <!--別名是一個(gè)較短的Java 類(lèi)型的名稱(chēng) --> <typeAliases> <typeAlias type="com.store.base.model.StoreUser" alias="User"></typeAlias> <typeAlias type="com.store.base.secondmodel.pratice.model.Product" alias="Product"></typeAlias> <typeAlias type="com.store.base.secondmodel.base.Page" alias="Page"></typeAlias> </typeAliases> <!-- 插件配置,這邊為mybatis配置分頁(yè)攔截器,這個(gè)分頁(yè)攔截器需要我們自己實(shí)現(xiàn) --> <plugins> <plugin interceptor="com.store.base.secondmodel.base.pageinterceptor.PaginationInterceptor" /> </plugins> </configuration>
一個(gè)ProductMapper.xml作為測(cè)試對(duì)象,這個(gè)mapper文件就簡(jiǎn)單配置一個(gè)需要用到的查詢(xún)語(yǔ)句
<?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" > <mapper namespace="com.store.base.secondmodel.pratice.dao.ProductDao" > <sql id="baseColumns" > id, product_name as productName, product_no as productNo, price as price </sql> <select id="findList" resultType="com.store.base.secondmodel.pratice.model.Product"> select <include refid="baseColumns"/> from t_store_product </select> </mapper>
第二步:接下去主要針對(duì)這個(gè)分頁(yè)攔截器進(jìn)行深入分析學(xué)習(xí),主要有以下幾個(gè)類(lèi)和其對(duì)應(yīng)接口
(1)BaseInterceptor 攔截器基礎(chǔ)類(lèi)
(2)PaginationInterceptor 我們要使用的分頁(yè)插件類(lèi),繼承上面基礎(chǔ)類(lèi)
(3)SQLHelper 主要是用來(lái)提前執(zhí)行count語(yǔ)句,還有就是獲取整個(gè)完整的分頁(yè)語(yǔ)句
(4)Dialect,MysqlDialect,主要用來(lái)數(shù)據(jù)庫(kù)是否支持limit語(yǔ)句,然后封裝完整limit語(yǔ)句
以下是這幾個(gè)類(lèi)的分享展示
BaseInterceptor.java
package com.store.base.secondmodel.base.pageinterceptor; import java.io.Serializable; import java.util.Properties; import org.apache.ibatis.logging.Log; import org.apache.ibatis.logging.LogFactory; import org.apache.ibatis.plugin.Interceptor; import com.store.base.secondmodel.base.Global; import com.store.base.secondmodel.base.Page; import com.store.base.secondmodel.base.dialect.Dialect; import com.store.base.secondmodel.base.dialect.MySQLDialect; import com.store.base.util.Reflections; /** * Mybatis分頁(yè)攔截器基類(lèi) * @author yiyong_wu * */ public abstract class BaseInterceptor implements Interceptor, Serializable { private static final long serialVersionUID = 1L; protected static final String PAGE = "page"; protected static final String DELEGATE = "delegate"; protected static final String MAPPED_STATEMENT = "mappedStatement"; protected Log log = LogFactory.getLog(this.getClass()); protected Dialect DIALECT; /** * 對(duì)參數(shù)進(jìn)行轉(zhuǎn)換和檢查 * @param parameterObject 參數(shù)對(duì)象 * @param page 分頁(yè)對(duì)象 * @return 分頁(yè)對(duì)象 * @throws NoSuchFieldException 無(wú)法找到參數(shù) */ @SuppressWarnings("unchecked") protected static Page<Object> convertParameter(Object parameterObject, Page<Object> page) { try{ if (parameterObject instanceof Page) { return (Page<Object>) parameterObject; } else { return (Page<Object>)Reflections.getFieldValue(parameterObject, PAGE); } }catch (Exception e) { return null; } } /** * 設(shè)置屬性,支持自定義方言類(lèi)和制定數(shù)據(jù)庫(kù)的方式 * <code>dialectClass</code>,自定義方言類(lèi)??梢圆慌渲眠@項(xiàng) * <ode>dbms</ode> 數(shù)據(jù)庫(kù)類(lèi)型,插件支持的數(shù)據(jù)庫(kù) * <code>sqlPattern</code> 需要攔截的SQL ID * @param p 屬性 */ protected void initProperties(Properties p) { Dialect dialect = null; String dbType = Global.getConfig("jdbc.type"); if("mysql".equals(dbType)){ dialect = new MySQLDialect(); } if (dialect == null) { throw new RuntimeException("mybatis dialect error."); } DIALECT = dialect; } }
PaginationInterceptor.java
package com.store.base.secondmodel.base.pageinterceptor; import java.util.Properties; import org.apache.ibatis.executor.Executor; import org.apache.ibatis.mapping.BoundSql; import org.apache.ibatis.mapping.MappedStatement; import org.apache.ibatis.mapping.SqlSource; import org.apache.ibatis.plugin.Intercepts; import org.apache.ibatis.plugin.Invocation; import org.apache.ibatis.plugin.Plugin; import org.apache.ibatis.plugin.Signature; import org.apache.ibatis.reflection.MetaObject; import org.apache.ibatis.session.ResultHandler; import org.apache.ibatis.session.RowBounds; import com.store.base.secondmodel.base.Page; import com.store.base.secondmodel.base.util.StringUtils; import com.store.base.util.Reflections; /** * 數(shù)據(jù)庫(kù)分頁(yè)插件,只攔截查詢(xún)語(yǔ)句. * @author yiyong_wu * */ @Intercepts({ @Signature(type = Executor.class, method = "query", args = { MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class }) }) public class PaginationInterceptor extends BaseInterceptor { private static final long serialVersionUID = 1L; @Override public Object intercept(Invocation invocation) throws Throwable { final MappedStatement mappedStatement = (MappedStatement) invocation.getArgs()[0]; Object parameter = invocation.getArgs()[1]; BoundSql boundSql = mappedStatement.getBoundSql(parameter); Object parameterObject = boundSql.getParameterObject(); // 獲取分頁(yè)參數(shù)對(duì)象 Page<Object> page = null; if (parameterObject != null) { page = convertParameter(parameterObject, page); } // 如果設(shè)置了分頁(yè)對(duì)象,則進(jìn)行分頁(yè) if (page != null && page.getPageSize() != -1) { if (StringUtils.isBlank(boundSql.getSql())) { return null; } String originalSql = boundSql.getSql().trim(); // 得到總記錄數(shù) page.setCount(SQLHelper.getCount(originalSql, null,mappedStatement, parameterObject, boundSql, log)); // 分頁(yè)查詢(xún) 本地化對(duì)象 修改數(shù)據(jù)庫(kù)注意修改實(shí)現(xiàn) String pageSql = SQLHelper.generatePageSql(originalSql, page,DIALECT); invocation.getArgs()[2] = new RowBounds(RowBounds.NO_ROW_OFFSET,RowBounds.NO_ROW_LIMIT); BoundSql newBoundSql = new BoundSql( mappedStatement.getConfiguration(), pageSql, boundSql.getParameterMappings(), boundSql.getParameterObject()); // 解決MyBatis 分頁(yè)foreach 參數(shù)失效 start if (Reflections.getFieldValue(boundSql, "metaParameters") != null) { MetaObject mo = (MetaObject) Reflections.getFieldValue( boundSql, "metaParameters"); Reflections.setFieldValue(newBoundSql, "metaParameters", mo); } // 解決MyBatis 分頁(yè)foreach 參數(shù)失效 end MappedStatement newMs = copyFromMappedStatement(mappedStatement,new BoundSqlSqlSource(newBoundSql)); invocation.getArgs()[0] = newMs; } return invocation.proceed(); } @Override public Object plugin(Object target) { return Plugin.wrap(target, this); } @Override public void setProperties(Properties properties) { super.initProperties(properties); } private MappedStatement copyFromMappedStatement(MappedStatement ms, SqlSource newSqlSource) { MappedStatement.Builder builder = new MappedStatement.Builder( ms.getConfiguration(), ms.getId(), newSqlSource, ms.getSqlCommandType()); builder.resource(ms.getResource()); builder.fetchSize(ms.getFetchSize()); builder.statementType(ms.getStatementType()); builder.keyGenerator(ms.getKeyGenerator()); if (ms.getKeyProperties() != null) { for (String keyProperty : ms.getKeyProperties()) { builder.keyProperty(keyProperty); } } builder.timeout(ms.getTimeout()); builder.parameterMap(ms.getParameterMap()); builder.resultMaps(ms.getResultMaps()); builder.cache(ms.getCache()); return builder.build(); } public static class BoundSqlSqlSource implements SqlSource { BoundSql boundSql; public BoundSqlSqlSource(BoundSql boundSql) { this.boundSql = boundSql; } @Override public BoundSql getBoundSql(Object parameterObject) { return boundSql; } } }
SQLHelper.java
package com.store.base.secondmodel.base.pageinterceptor; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.List; import java.util.regex.Matcher; import java.util.regex.Pattern; import org.apache.ibatis.executor.ErrorContext; import org.apache.ibatis.executor.ExecutorException; import org.apache.ibatis.logging.Log; import org.apache.ibatis.mapping.BoundSql; import org.apache.ibatis.mapping.MappedStatement; import org.apache.ibatis.mapping.ParameterMapping; import org.apache.ibatis.mapping.ParameterMode; import org.apache.ibatis.reflection.MetaObject; import org.apache.ibatis.reflection.property.PropertyTokenizer; import org.apache.ibatis.scripting.xmltags.ForEachSqlNode; import org.apache.ibatis.session.Configuration; import org.apache.ibatis.type.TypeHandler; import org.apache.ibatis.type.TypeHandlerRegistry; import com.store.base.secondmodel.base.Global; import com.store.base.secondmodel.base.Page; import com.store.base.secondmodel.base.dialect.Dialect; import com.store.base.secondmodel.base.util.StringUtils; import com.store.base.util.Reflections; /** * SQL工具類(lèi) * @author yiyong_wu * */ public class SQLHelper { /** * 默認(rèn)私有構(gòu)造函數(shù) */ private SQLHelper() { } /** * 對(duì)SQL參數(shù)(?)設(shè)值,參考o(jì)rg.apache.ibatis.executor.parameter.DefaultParameterHandler * * @param ps 表示預(yù)編譯的 SQL 語(yǔ)句的對(duì)象。 * @param mappedStatement MappedStatement * @param boundSql SQL * @param parameterObject 參數(shù)對(duì)象 * @throws java.sql.SQLException 數(shù)據(jù)庫(kù)異常 */ @SuppressWarnings("unchecked") public static void setParameters(PreparedStatement ps, MappedStatement mappedStatement, BoundSql boundSql, Object parameterObject) throws SQLException { ErrorContext.instance().activity("setting parameters").object(mappedStatement.getParameterMap().getId()); List<ParameterMapping> parameterMappings = boundSql.getParameterMappings(); if (parameterMappings != null) { Configuration configuration = mappedStatement.getConfiguration(); TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry(); MetaObject metaObject = parameterObject == null ? null : configuration.newMetaObject(parameterObject); for (int i = 0; i < parameterMappings.size(); i++) { ParameterMapping parameterMapping = parameterMappings.get(i); if (parameterMapping.getMode() != ParameterMode.OUT) { Object value; String propertyName = parameterMapping.getProperty(); PropertyTokenizer prop = new PropertyTokenizer(propertyName); if (parameterObject == null) { value = null; } else if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) { value = parameterObject; } else if (boundSql.hasAdditionalParameter(propertyName)) { value = boundSql.getAdditionalParameter(propertyName); } else if (propertyName.startsWith(ForEachSqlNode.ITEM_PREFIX) && boundSql.hasAdditionalParameter(prop.getName())) { value = boundSql.getAdditionalParameter(prop.getName()); if (value != null) { value = configuration.newMetaObject(value).getValue(propertyName.substring(prop.getName().length())); } } else { value = metaObject == null ? null : metaObject.getValue(propertyName); } @SuppressWarnings("rawtypes") TypeHandler typeHandler = parameterMapping.getTypeHandler(); if (typeHandler == null) { throw new ExecutorException("There was no TypeHandler found for parameter " + propertyName + " of statement " + mappedStatement.getId()); } typeHandler.setParameter(ps, i + 1, value, parameterMapping.getJdbcType()); } } } } /** * 查詢(xún)總紀(jì)錄數(shù) * @param sql SQL語(yǔ)句 * @param connection 數(shù)據(jù)庫(kù)連接 * @param mappedStatement mapped * @param parameterObject 參數(shù) * @param boundSql boundSql * @return 總記錄數(shù) * @throws SQLException sql查詢(xún)錯(cuò)誤 */ public static int getCount(final String sql, final Connection connection, final MappedStatement mappedStatement, final Object parameterObject, final BoundSql boundSql, Log log) throws SQLException { String dbName = Global.getConfig("jdbc.type"); final String countSql; if("oracle".equals(dbName)){ countSql = "select count(1) from (" + sql + ") tmp_count"; }else{ countSql = "select count(1) from (" + removeOrders(sql) + ") tmp_count"; } Connection conn = connection; PreparedStatement ps = null; ResultSet rs = null; try { if (log.isDebugEnabled()) { log.debug("COUNT SQL: " + StringUtils.replaceEach(countSql, new String[]{"\n","\t"}, new String[]{" "," "})); } if (conn == null){ conn = mappedStatement.getConfiguration().getEnvironment().getDataSource().getConnection(); } ps = conn.prepareStatement(countSql); BoundSql countBS = new BoundSql(mappedStatement.getConfiguration(), countSql, boundSql.getParameterMappings(), parameterObject); //解決MyBatis 分頁(yè)foreach 參數(shù)失效 start if (Reflections.getFieldValue(boundSql, "metaParameters") != null) { MetaObject mo = (MetaObject) Reflections.getFieldValue(boundSql, "metaParameters"); Reflections.setFieldValue(countBS, "metaParameters", mo); } //解決MyBatis 分頁(yè)foreach 參數(shù)失效 end SQLHelper.setParameters(ps, mappedStatement, countBS, parameterObject); rs = ps.executeQuery(); int count = 0; if (rs.next()) { count = rs.getInt(1); } return count; } finally { if (rs != null) { rs.close(); } if (ps != null) { ps.close(); } if (conn != null) { conn.close(); } } } /** * 根據(jù)數(shù)據(jù)庫(kù)方言,生成特定的分頁(yè)sql * @param sql Mapper中的Sql語(yǔ)句 * @param page 分頁(yè)對(duì)象 * @param dialect 方言類(lèi)型 * @return 分頁(yè)SQL */ public static String generatePageSql(String sql, Page<Object> page, Dialect dialect) { if (dialect.supportsLimit()) { return dialect.getLimitString(sql, page.getFirstResult(), page.getMaxResults()); } else { return sql; } } /** * 去除qlString的select子句。 * @param hql * @return */ @SuppressWarnings("unused") private static String removeSelect(String qlString){ int beginPos = qlString.toLowerCase().indexOf("from"); return qlString.substring(beginPos); } /** * 去除hql的orderBy子句。 * @param hql * @return */ private static String removeOrders(String qlString) { Pattern p = Pattern.compile("order\\s*by[\\w|\\W|\\s|\\S]*", Pattern.CASE_INSENSITIVE); Matcher m = p.matcher(qlString); StringBuffer sb = new StringBuffer(); while (m.find()) { m.appendReplacement(sb, ""); } m.appendTail(sb); return sb.toString(); } }
Dialect.java 接口
package com.store.base.secondmodel.base.dialect; /** * 類(lèi)似hibernate的Dialect,但只精簡(jiǎn)出分頁(yè)部分 * @author yiyong_wu * */ public interface Dialect { /** * 數(shù)據(jù)庫(kù)本身是否支持分頁(yè)當(dāng)前的分頁(yè)查詢(xún)方式 * 如果數(shù)據(jù)庫(kù)不支持的話,則不進(jìn)行數(shù)據(jù)庫(kù)分頁(yè) * * @return true:支持當(dāng)前的分頁(yè)查詢(xún)方式 */ public boolean supportsLimit(); /** * 將sql轉(zhuǎn)換為分頁(yè)SQL,分別調(diào)用分頁(yè)sql * * @param sql SQL語(yǔ)句 * @param offset 開(kāi)始條數(shù) * @param limit 每頁(yè)顯示多少紀(jì)錄條數(shù) * @return 分頁(yè)查詢(xún)的sql */ public String getLimitString(String sql, int offset, int limit); }
MySQLDialect.java
package com.store.base.secondmodel.base.dialect; /** * Mysql方言的實(shí)現(xiàn) * @author yiyong_wu * */ public class MySQLDialect implements Dialect { @Override public boolean supportsLimit() { return true; } @Override public String getLimitString(String sql, int offset, int limit) { return getLimitString(sql, offset, Integer.toString(offset),Integer.toString(limit)); } /** * 將sql變成分頁(yè)sql語(yǔ)句,提供將offset及l(fā)imit使用占位符號(hào)(placeholder)替換. * <pre> * 如mysql * dialect.getLimitString("select * from user", 12, ":offset",0,":limit") 將返回 * select * from user limit :offset,:limit * </pre> * * @param sql 實(shí)際SQL語(yǔ)句 * @param offset 分頁(yè)開(kāi)始紀(jì)錄條數(shù) * @param offsetPlaceholder 分頁(yè)開(kāi)始紀(jì)錄條數(shù)-占位符號(hào) * @param limitPlaceholder 分頁(yè)紀(jì)錄條數(shù)占位符號(hào) * @return 包含占位符的分頁(yè)sql */ public String getLimitString(String sql, int offset, String offsetPlaceholder, String limitPlaceholder) { StringBuilder stringBuilder = new StringBuilder(sql); stringBuilder.append(" limit "); if (offset > 0) { stringBuilder.append(offsetPlaceholder).append(",").append(limitPlaceholder); } else { stringBuilder.append(limitPlaceholder); } return stringBuilder.toString(); } }
差不多到這邊已經(jīng)把整塊分頁(yè)怎么實(shí)現(xiàn)的給分享完了,但是我們還有更重要的任務(wù),想要整個(gè)東西跑起來(lái),肯定還要有基礎(chǔ)工作要做,接下去我們分析整套Page對(duì)象以及它所依據(jù)的三層架構(gòu),還是用product作為實(shí)體進(jìn)行分析。一整套三層架構(gòu)講下來(lái),收獲肯定又滿(mǎn)滿(mǎn)的。我們依次從entity->dao->service的順序講下來(lái)。
首先,針對(duì)我們的實(shí)體得繼承兩個(gè)抽象實(shí)體類(lèi)BaseEntity 與 DataEntity
BaseEntity.java 主要放置Page成員變量,繼承它后就可以每個(gè)實(shí)體都擁有這個(gè)成員變量
package com.store.base.secondmodel.base; import java.io.Serializable; import java.util.Map; import javax.xml.bind.annotation.XmlTransient; import org.apache.commons.lang3.StringUtils; import org.apache.commons.lang3.builder.ReflectionToStringBuilder; import com.fasterxml.jackson.annotation.JsonIgnore; import com.google.common.collect.Maps; import com.store.base.model.StoreUser; /** * 最頂層的Entity * @author yiyong_wu * * @param <T> */ public abstract class BaseEntity<T> implements Serializable { private static final long serialVersionUID = 1L; /** * 刪除標(biāo)記(0:正常;1:刪除;2:審核;) */ public static final String DEL_FLAG_NORMAL = "0"; public static final String DEL_FLAG_DELETE = "1"; public static final String DEL_FLAG_AUDIT = "2"; /** * 實(shí)體編號(hào)(唯一標(biāo)識(shí)) */ protected String id; /** * 當(dāng)前用戶(hù) */ protected StoreUser currentUser; /** * 當(dāng)前實(shí)體分頁(yè)對(duì)象 */ protected Page<T> page; /** * 自定義SQL(SQL標(biāo)識(shí),SQL內(nèi)容) */ private Map<String, String> sqlMap; public BaseEntity() { } public BaseEntity(String id) { this(); this.id = id; } public String getId() { return id; } public void setId(String id) { this.id = id; } /** * 這個(gè)主要針對(duì)shiro執(zhí)行插入更新的時(shí)候會(huì)調(diào)用,獲取當(dāng)前的用戶(hù) * @return */ @JsonIgnore @XmlTransient public StoreUser getCurrentUser() { if(currentUser == null){ // currentUser = UserUtils.getUser(); } return currentUser; } public void setCurrentUser(StoreUser currentUser) { this.currentUser = currentUser; } @JsonIgnore @XmlTransient public Page<T> getPage() { if (page == null){ page = new Page<>(); } return page; } public Page<T> setPage(Page<T> page) { this.page = page; return page; } @JsonIgnore @XmlTransient public Map<String, String> getSqlMap() { if (sqlMap == null){ sqlMap = Maps.newHashMap(); } return sqlMap; } public void setSqlMap(Map<String, String> sqlMap) { this.sqlMap = sqlMap; } /** * 插入之前執(zhí)行方法,子類(lèi)實(shí)現(xiàn) */ public abstract void preInsert(); /** * 更新之前執(zhí)行方法,子類(lèi)實(shí)現(xiàn) */ public abstract void preUpdate(); /** * 是否是新記錄(默認(rèn):false),調(diào)用setIsNewRecord()設(shè)置新記錄,使用自定義ID。 * 設(shè)置為true后強(qiáng)制執(zhí)行插入語(yǔ)句,ID不會(huì)自動(dòng)生成,需從手動(dòng)傳入。 * @return */ public boolean getIsNewRecord() { return StringUtils.isBlank(getId()); } /** * 全局變量對(duì)象 */ @JsonIgnore public Global getGlobal() { return Global.getInstance(); } /** * 獲取數(shù)據(jù)庫(kù)名稱(chēng) */ @JsonIgnore public String getDbName(){ return Global.getConfig("jdbc.type"); } @Override public String toString() { return ReflectionToStringBuilder.toString(this); } }
DataEntity.java,主要存儲(chǔ)更新刪除時(shí)間,創(chuàng)建用戶(hù),更新用戶(hù),邏輯刪除標(biāo)志等
package com.store.base.secondmodel.base; import java.util.Date; import org.hibernate.validator.constraints.Length; import com.fasterxml.jackson.annotation.JsonFormat; import com.fasterxml.jackson.annotation.JsonIgnore; import com.store.base.model.StoreUser; /** * 數(shù)據(jù)Entity * @author yiyong_wu * * @param <T> */ public abstract class DataEntity<T> extends BaseEntity<T> { private static final long serialVersionUID = 1L; protected StoreUser createBy; // 創(chuàng)建者 protected Date createDate; // 創(chuàng)建日期 protected StoreUser updateBy; // 更新者 protected Date updateDate; // 更新日期 protected String delFlag; // 刪除標(biāo)記(0:正常;1:刪除;2:審核) public DataEntity() { super(); this.delFlag = DEL_FLAG_NORMAL; } public DataEntity(String id) { super(id); } /** * 插入之前執(zhí)行方法,需要手動(dòng)調(diào)用 */ @Override public void preInsert() { // 不限制ID為UUID,調(diào)用setIsNewRecord()使用自定義ID // User user = UserUtils.getUser(); // if (StringUtils.isNotBlank(user.getId())) { // this.updateBy = user; // this.createBy = user; // } this.updateDate = new Date(); this.createDate = this.updateDate; } /** * 更新之前執(zhí)行方法,需要手動(dòng)調(diào)用 */ @Override public void preUpdate() { // User user = UserUtils.getUser(); // if (StringUtils.isNotBlank(user.getId())) { // this.updateBy = user; // } this.updateDate = new Date(); } // @JsonIgnore public StoreUser getCreateBy() { return createBy; } public void setCreateBy(StoreUser createBy) { this.createBy = createBy; } @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss") public Date getCreateDate() { return createDate; } public void setCreateDate(Date createDate) { this.createDate = createDate; } // @JsonIgnore public StoreUser getUpdateBy() { return updateBy; } public void setUpdateBy(StoreUser updateBy) { this.updateBy = updateBy; } @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss") public Date getUpdateDate() { return updateDate; } public void setUpdateDate(Date updateDate) { this.updateDate = updateDate; } @JsonIgnore @Length(min = 1, max = 1) public String getDelFlag() { return delFlag; } public void setDelFlag(String delFlag) { this.delFlag = delFlag; } }
Product.java 產(chǎn)品類(lèi)
package com.store.base.secondmodel.pratice.model; import com.store.base.secondmodel.base.DataEntity; /** *產(chǎn)品基礎(chǔ)類(lèi) *2016年10月11日 *yiyong_wu */ public class Product extends DataEntity<Product>{ private static final long serialVersionUID = 1L; private String productName; private float price; private String productNo; public String getProductName() { return productName; } public void setProductName(String productName) { this.productName = productName; } public float getPrice() { return price; } public void setPrice(float price) { this.price = price; } public String getProductNo() { return productNo; } public void setProductNo(String productNo) { this.productNo = productNo; } }
怎么樣,是不是看到很復(fù)雜的一個(gè)實(shí)體繼承連關(guān)系,不過(guò)這有什么,越復(fù)雜就會(huì)越完整。接下來(lái)我就看看dao層,同樣是三層,準(zhǔn)備好接受洗禮吧
BaseDao.java 預(yù)留接口
package com.store.base.secondmodel.base; /** * 最頂層的DAO接口 * @author yiyong_wu * */ public interface BaseDao { } CrudDao.java 針對(duì)增刪改查的一個(gè)dao接口層 [java] view plain copy print?在CODE上查看代碼片派生到我的代碼片 package com.store.base.secondmodel.base; import java.util.List; /** * 定義增刪改查的DAO接口 * @author yiyong_wu * * @param <T> */ public interface CrudDao<T> extends BaseDao { /** * 獲取單條數(shù)據(jù) * @param id * @return */ public T get(String id); /** * 獲取單條數(shù)據(jù) * @param entity * @return */ public T get(T entity); /** * 查詢(xún)數(shù)據(jù)列表,如果需要分頁(yè),請(qǐng)?jiān)O(shè)置分頁(yè)對(duì)象,如:entity.setPage(new Page<T>()); * @param entity * @return */ public List<T> findList(T entity); /** * 查詢(xún)所有數(shù)據(jù)列表 * @param entity * @return */ public List<T> findAllList(T entity); /** * 查詢(xún)所有數(shù)據(jù)列表 * @see public List<T> findAllList(T entity) * @return public List<T> findAllList(); */ /** * 插入數(shù)據(jù) * @param entity * @return */ public int insert(T entity); /** * 更新數(shù)據(jù) * @param entity * @return */ public int update(T entity); /** * 刪除數(shù)據(jù)(一般為邏輯刪除,更新del_flag字段為1) * @param id * @see public int delete(T entity) * @return */ public int delete(String id); /** * 刪除數(shù)據(jù)(一般為邏輯刪除,更新del_flag字段為1) * @param entity * @return */ public int delete(T entity); }
ProductDao.java mybatis對(duì)應(yīng)的接口mapper,同時(shí)也是dao實(shí)現(xiàn),這邊需要自定一個(gè)注解@MyBatisRepository
package com.store.base.secondmodel.pratice.dao; import com.store.base.secondmodel.base.CrudDao; import com.store.base.secondmodel.base.MyBatisRepository; import com.store.base.secondmodel.pratice.model.Product; /** *TODO *2016年10月11日 *yiyong_wu */ @MyBatisRepository public interface ProductDao extends CrudDao<Product>{ }
自定義注解MyBatisRepository.java,跟自定義注解相關(guān),這里就不做過(guò)多的解讀,網(wǎng)上資料一堆
package com.store.base.secondmodel.base; import java.lang.annotation.Documented; import java.lang.annotation.Retention; import java.lang.annotation.Target; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.ElementType; import org.springframework.stereotype.Component; /** * 標(biāo)識(shí)MyBatis的DAO,方便{@link org.mybatis.spring.mapper.MapperScannerConfigurer}的掃描。 * * 請(qǐng)注意要在spring的配置文件中配置掃描該注解類(lèi)的配置 * *<bean id="mapperScannerConfigurer" class="org.mybatis.spring.mapper.MapperScannerConfigurer"> *<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" /> *<property name="basePackage" value="com.store.base.secondmodel" /> *<property name="annotationClass" value="com.store.base.secondmodel.base.MyBatisRepository" /> *</bean> * @author yiyong_wu * */ @Retention(RetentionPolicy.RUNTIME) @Target(ElementType.TYPE) @Documented @Component public @interface MyBatisRepository { String value() default ""; }
注意:跟ProductDao.java聯(lián)系比較大的是ProductMapper.xml文件,大家可以看到上面那個(gè)配置文件的namespace是指向這個(gè)dao的路徑的。
接下來(lái)我們就進(jìn)入最后的service分析了,一樣還是三層繼承
BaseService.java
package com.store.base.secondmodel.base; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.transaction.annotation.Transactional; /** * Service的最頂層父類(lèi) * @author yiyong_wu * */ @Transactional(readOnly = true) public abstract class BaseService { //日志記錄用的 protected Logger logger = LoggerFactory.getLogger(getClass()); }
CrudService.java 增刪改查相關(guān)的業(yè)務(wù)接口實(shí)現(xiàn)
package com.store.base.secondmodel.base; import java.util.List; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.transaction.annotation.Transactional; /** * 增刪改查Service基類(lèi) * @author yiyong_wu * * @param <D> * @param <T> */ public abstract class CrudService<D extends CrudDao<T>, T extends DataEntity<T>> extends BaseService { /** * 持久層對(duì)象 */ @Autowired protected D dao; /** * 獲取單條數(shù)據(jù) * @param id * @return */ public T get(String id) { return dao.get(id); } /** * 獲取單條數(shù)據(jù) * @param entity * @return */ public T get(T entity) { return dao.get(entity); } /** * 查詢(xún)列表數(shù)據(jù) * @param entity * @return */ public List<T> findList(T entity) { return dao.findList(entity); } /** * 查詢(xún)分頁(yè)數(shù)據(jù) * @param page 分頁(yè)對(duì)象 * @param entity * @return */ public Page<T> findPage(Page<T> page, T entity) { entity.setPage(page); page.setList(dao.findList(entity)); return page; } /** * 保存數(shù)據(jù)(插入或更新) * @param entity */ @Transactional(readOnly = false) public void save(T entity) { if (entity.getIsNewRecord()){ entity.preInsert(); dao.insert(entity); }else{ entity.preUpdate(); dao.update(entity); } } /** * 刪除數(shù)據(jù) * @param entity */ @Transactional(readOnly = false) public void delete(T entity) { dao.delete(entity); } }
ProductService.java,去繼承CrudService接口,注意起注入dao和實(shí)體類(lèi)型的一種模式
package com.store.base.secondmodel.pratice.service; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import com.store.base.secondmodel.base.CrudService; import com.store.base.secondmodel.pratice.dao.ProductDao; import com.store.base.secondmodel.pratice.model.Product; /** *TODO *2016年10月11日 *yiyong_wu */ @Service @Transactional(readOnly = true) public class ProductService extends CrudService<ProductDao,Product>{ }
我想看到這里的同志已經(jīng)很不耐煩了。但是如果你錯(cuò)過(guò)接下去的一段,基本上剛才看的就快等于白看了,革命的勝利就在后半段,因?yàn)檎麄€(gè)分頁(yè)功能?chē)@的就是一個(gè)Page對(duì)象,重磅內(nèi)容終于要出來(lái)了,當(dāng)你把Page對(duì)象填充到剛才那個(gè)BaseEntity上的時(shí)候,你會(huì)發(fā)現(xiàn)一切就完整起來(lái)了,廢話不多說(shuō),Page對(duì)象如下
package com.store.base.secondmodel.base; import java.io.Serializable; import java.util.ArrayList; import java.util.List; import java.util.regex.Pattern; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.fasterxml.jackson.annotation.JsonIgnore; import com.store.base.secondmodel.base.util.CookieUtils; import com.store.base.secondmodel.base.util.StringUtils; /** * 分頁(yè)類(lèi) * @author yiyong_wu * * @param <T> */ public class Page<T> implements Serializable{ private static final long serialVersionUID = 1L; private int pageNo = 1; // 當(dāng)前頁(yè)碼 private int pageSize = Integer.parseInt(Global.getConfig("page.pageSize")); // 頁(yè)面大小,設(shè)置為“-1”表示不進(jìn)行分頁(yè)(分頁(yè)無(wú)效) private long count;// 總記錄數(shù),設(shè)置為“-1”表示不查詢(xún)總數(shù) private int first;// 首頁(yè)索引 private int last;// 尾頁(yè)索引 private int prev;// 上一頁(yè)索引 private int next;// 下一頁(yè)索引 private boolean firstPage;//是否是第一頁(yè) private boolean lastPage;//是否是最后一頁(yè) private int length = 6;// 顯示頁(yè)面長(zhǎng)度 private int slider = 1;// 前后顯示頁(yè)面長(zhǎng)度 private List<T> list = new ArrayList<>(); private String orderBy = ""; // 標(biāo)準(zhǔn)查詢(xún)有效, 實(shí)例: updatedate desc, name asc private String funcName = "page"; // 設(shè)置點(diǎn)擊頁(yè)碼調(diào)用的js函數(shù)名稱(chēng),默認(rèn)為page,在一頁(yè)有多個(gè)分頁(yè)對(duì)象時(shí)使用。 private String funcParam = ""; // 函數(shù)的附加參數(shù),第三個(gè)參數(shù)值。 private String message = ""; // 設(shè)置提示消息,顯示在“共n條”之后 public Page() { this.pageSize = -1; } /** * 構(gòu)造方法 * @param request 傳遞 repage 參數(shù),來(lái)記住頁(yè)碼 * @param response 用于設(shè)置 Cookie,記住頁(yè)碼 */ public Page(HttpServletRequest request, HttpServletResponse response){ this(request, response, -2); } /** * 構(gòu)造方法 * @param request 傳遞 repage 參數(shù),來(lái)記住頁(yè)碼 * @param response 用于設(shè)置 Cookie,記住頁(yè)碼 * @param defaultPageSize 默認(rèn)分頁(yè)大小,如果傳遞 -1 則為不分頁(yè),返回所有數(shù)據(jù) */ public Page(HttpServletRequest request, HttpServletResponse response, int defaultPageSize){ // 設(shè)置頁(yè)碼參數(shù)(傳遞repage參數(shù),來(lái)記住頁(yè)碼) String no = request.getParameter("pageNo"); if (StringUtils.isNumeric(no)){ CookieUtils.setCookie(response, "pageNo", no); this.setPageNo(Integer.parseInt(no)); }else if (request.getParameter("repage")!=null){ no = CookieUtils.getCookie(request, "pageNo"); if (StringUtils.isNumeric(no)){ this.setPageNo(Integer.parseInt(no)); } } // 設(shè)置頁(yè)面大小參數(shù)(傳遞repage參數(shù),來(lái)記住頁(yè)碼大?。? String size = request.getParameter("pageSize"); if (StringUtils.isNumeric(size)){ CookieUtils.setCookie(response, "pageSize", size); this.setPageSize(Integer.parseInt(size)); }else if (request.getParameter("repage")!=null){ no = CookieUtils.getCookie(request, "pageSize"); if (StringUtils.isNumeric(size)){ this.setPageSize(Integer.parseInt(size)); } }else if (defaultPageSize != -2){ this.pageSize = defaultPageSize; } // 設(shè)置排序參數(shù) String orderBy = request.getParameter("orderBy"); if (StringUtils.isNotBlank(orderBy)){ this.setOrderBy(orderBy); } } /** * 構(gòu)造方法 * @param pageNo 當(dāng)前頁(yè)碼 * @param pageSize 分頁(yè)大小 */ public Page(int pageNo, int pageSize) { this(pageNo, pageSize, 0); } /** * 構(gòu)造方法 * @param pageNo 當(dāng)前頁(yè)碼 * @param pageSize 分頁(yè)大小 * @param count 數(shù)據(jù)條數(shù) */ public Page(int pageNo, int pageSize, long count) { this(pageNo, pageSize, count, new ArrayList<T>()); } /** * 構(gòu)造方法 * @param pageNo 當(dāng)前頁(yè)碼 * @param pageSize 分頁(yè)大小 * @param count 數(shù)據(jù)條數(shù) * @param list 本頁(yè)數(shù)據(jù)對(duì)象列表 */ public Page(int pageNo, int pageSize, long count, List<T> list) { this.setCount(count); this.setPageNo(pageNo); this.pageSize = pageSize; this.list = list; } /** * 初始化參數(shù) */ public void initialize(){ //1 this.first = 1; this.last = (int)(count / (this.pageSize < 1 ? 20 : this.pageSize) + first - 1); if (this.count % this.pageSize != 0 || this.last == 0) { this.last++; } if (this.last < this.first) { this.last = this.first; } if (this.pageNo <= 1) { this.pageNo = this.first; this.firstPage=true; } if (this.pageNo >= this.last) { this.pageNo = this.last; this.lastPage=true; } if (this.pageNo < this.last - 1) { this.next = this.pageNo + 1; } else { this.next = this.last; } if (this.pageNo > 1) { this.prev = this.pageNo - 1; } else { this.prev = this.first; } //2 if (this.pageNo < this.first) {// 如果當(dāng)前頁(yè)小于首頁(yè) this.pageNo = this.first; } if (this.pageNo > this.last) {// 如果當(dāng)前頁(yè)大于尾頁(yè) this.pageNo = this.last; } } /** * 默認(rèn)輸出當(dāng)前分頁(yè)標(biāo)簽 * <div class="page">${page}</div> */ @Override public String toString() { StringBuilder sb = new StringBuilder(); if (pageNo == first) {// 如果是首頁(yè) sb.append("<li class=\"disabled\"><a href=\"javascript:\">« 上一頁(yè)</a></li>\n"); } else { sb.append("<li><a href=\"javascript:\" onclick=\""+funcName+"("+prev+","+pageSize+",'"+funcParam+"');\">« 上一頁(yè)</a></li>\n"); } int begin = pageNo - (length / 2); if (begin < first) { begin = first; } int end = begin + length - 1; if (end >= last) { end = last; begin = end - length + 1; if (begin < first) { begin = first; } } if (begin > first) { int i = 0; for (i = first; i < first + slider && i < begin; i++) { sb.append("<li><a href=\"javascript:\" onclick=\""+funcName+"("+i+","+pageSize+",'"+funcParam+"');\">" + (i + 1 - first) + "</a></li>\n"); } if (i < begin) { sb.append("<li class=\"disabled\"><a href=\"javascript:\">...</a></li>\n"); } } for (int i = begin; i <= end; i++) { if (i == pageNo) { sb.append("<li class=\"active\"><a href=\"javascript:\">" + (i + 1 - first) + "</a></li>\n"); } else { sb.append("<li><a href=\"javascript:\" onclick=\""+funcName+"("+i+","+pageSize+",'"+funcParam+"');\">" + (i + 1 - first) + "</a></li>\n"); } } if (last - end > slider) { sb.append("<li class=\"disabled\"><a href=\"javascript:\">...</a></li>\n"); end = last - slider; } for (int i = end + 1; i <= last; i++) { sb.append("<li><a href=\"javascript:\" onclick=\""+funcName+"("+i+","+pageSize+",'"+funcParam+"');\">" + (i + 1 - first) + "</a></li>\n"); } if (pageNo == last) { sb.append("<li class=\"disabled\"><a href=\"javascript:\">下一頁(yè) »</a></li>\n"); } else { sb.append("<li><a href=\"javascript:\" onclick=\""+funcName+"("+next+","+pageSize+",'"+funcParam+"');\">" + "下一頁(yè) »</a></li>\n"); } return sb.toString(); } /** * 獲取分頁(yè)HTML代碼 * @return */ public String getHtml(){ return toString(); } /** * 獲取設(shè)置總數(shù) * @return */ public long getCount() { return count; } /** * 設(shè)置數(shù)據(jù)總數(shù) * @param count */ public void setCount(long count) { this.count = count; if (pageSize >= count){ pageNo = 1; } } /** * 獲取當(dāng)前頁(yè)碼 * @return */ public int getPageNo() { return pageNo; } /** * 設(shè)置當(dāng)前頁(yè)碼 * @param pageNo */ public void setPageNo(int pageNo) { this.pageNo = pageNo; } /** * 獲取頁(yè)面大小 * @return */ public int getPageSize() { return pageSize; } /** * 設(shè)置頁(yè)面大?。ㄗ畲?00)// > 500 ? 500 : pageSize; * @param pageSize */ public void setPageSize(int pageSize) { this.pageSize = pageSize <= 0 ? 10 : pageSize; } /** * 首頁(yè)索引 * @return */ @JsonIgnore public int getFirst() { return first; } /** * 尾頁(yè)索引 * @return */ @JsonIgnore public int getLast() { return last; } /** * 獲取頁(yè)面總數(shù) * @return getLast(); */ @JsonIgnore public int getTotalPage() { return getLast(); } /** * 是否為第一頁(yè) * @return */ @JsonIgnore public boolean isFirstPage() { return firstPage; } /** * 是否為最后一頁(yè) * @return */ @JsonIgnore public boolean isLastPage() { return lastPage; } /** * 上一頁(yè)索引值 * @return */ @JsonIgnore public int getPrev() { if (isFirstPage()) { return pageNo; } else { return pageNo - 1; } } /** * 下一頁(yè)索引值 * @return */ @JsonIgnore public int getNext() { if (isLastPage()) { return pageNo; } else { return pageNo + 1; } } /** * 獲取本頁(yè)數(shù)據(jù)對(duì)象列表 * @return List<T> */ public List<T> getList() { return list; } /** * 設(shè)置本頁(yè)數(shù)據(jù)對(duì)象列表 * @param list */ public Page<T> setList(List<T> list) { this.list = list; initialize(); return this; } /** * 獲取查詢(xún)排序字符串 * @return */ @JsonIgnore public String getOrderBy() { // SQL過(guò)濾,防止注入 String reg = "(?:')|(?:--)|(/\\*(?:.|[\\n\\r])*?\\*/)|" + "(\\b(select|update|and|or|delete|insert|trancate|char|into|substr|ascii|declare|exec|count|master|into|drop|execute)\\b)"; Pattern sqlPattern = Pattern.compile(reg, Pattern.CASE_INSENSITIVE); if (sqlPattern.matcher(orderBy).find()) { return ""; } return orderBy; } /** * 設(shè)置查詢(xún)排序,標(biāo)準(zhǔn)查詢(xún)有效, 實(shí)例: updatedate desc, name asc */ public void setOrderBy(String orderBy) { this.orderBy = orderBy; } /** * 獲取點(diǎn)擊頁(yè)碼調(diào)用的js函數(shù)名稱(chēng) * function ${page.funcName}(pageNo){location="${ctx}/list-${category.id}${urlSuffix}?pageNo="+i;} * @return */ @JsonIgnore public String getFuncName() { return funcName; } /** * 設(shè)置點(diǎn)擊頁(yè)碼調(diào)用的js函數(shù)名稱(chēng),默認(rèn)為page,在一頁(yè)有多個(gè)分頁(yè)對(duì)象時(shí)使用。 * @param funcName 默認(rèn)為page */ public void setFuncName(String funcName) { this.funcName = funcName; } /** * 獲取分頁(yè)函數(shù)的附加參數(shù) * @return */ @JsonIgnore public String getFuncParam() { return funcParam; } /** * 設(shè)置分頁(yè)函數(shù)的附加參數(shù) * @return */ public void setFuncParam(String funcParam) { this.funcParam = funcParam; } /** * 設(shè)置提示消息,顯示在“共n條”之后 * @param message */ public void setMessage(String message) { this.message = message; } /** * 分頁(yè)是否有效 * @return this.pageSize==-1 */ @JsonIgnore public boolean isDisabled() { return this.pageSize==-1; } /** * 是否進(jìn)行總數(shù)統(tǒng)計(jì) * @return this.count==-1 */ @JsonIgnore public boolean isNotCount() { return this.count==-1; } /** * 獲取 Hibernate FirstResult */ public int getFirstResult(){ int firstResult = (getPageNo() - 1) * getPageSize(); if (firstResult >= getCount()) { firstResult = 0; } return firstResult; } /** * 獲取 Hibernate MaxResults */ public int getMaxResults(){ return getPageSize(); } }
看完這個(gè)Page對(duì)象應(yīng)該稍微有點(diǎn)感覺(jué)了吧,然后我在胡亂貼一些相關(guān)用到的工具類(lèi)吧,工具類(lèi)的話我只稍微提一下,具體大家可以弄到自己的代碼上好好解讀。
PropertiesLoader.java 用來(lái)獲取resource文件夾下的常量配置文件
package com.store.base.secondmodel.base.util; import java.io.IOException; import java.io.InputStream; import java.util.NoSuchElementException; import java.util.Properties; import org.apache.commons.io.IOUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.core.io.DefaultResourceLoader; import org.springframework.core.io.Resource; import org.springframework.core.io.ResourceLoader; /** * Properties文件載入工具類(lèi). 可載入多個(gè)properties文件, * 相同的屬性在最后載入的文件中的值將會(huì)覆蓋之前的值,但以System的Property優(yōu)先. * @author yiyong_wu * */ public class PropertiesLoader { private static Logger logger = LoggerFactory.getLogger(PropertiesLoader.class); private static ResourceLoader resourceLoader = new DefaultResourceLoader(); private final Properties properties; public PropertiesLoader(String... resourcesPaths) { properties = loadProperties(resourcesPaths); } public Properties getProperties() { return properties; } /** * 取出Property,但以System的Property優(yōu)先,取不到返回空字符串. */ private String getValue(String key) { String systemProperty = System.getProperty(key); if (systemProperty != null) { return systemProperty; } if (properties.containsKey(key)) { return properties.getProperty(key); } return ""; } /** * 取出String類(lèi)型的Property,但以System的Property優(yōu)先,如果都為Null則拋出異常. */ public String getProperty(String key) { String value = getValue(key); if (value == null) { throw new NoSuchElementException(); } return value; } /** * 取出String類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null則返回Default值. */ public String getProperty(String key, String defaultValue) { String value = getValue(key); return value != null ? value : defaultValue; } /** * 取出Integer類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null或內(nèi)容錯(cuò)誤則拋出異常. */ public Integer getInteger(String key) { String value = getValue(key); if (value == null) { throw new NoSuchElementException(); } return Integer.valueOf(value); } /** * 取出Integer類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null則返回Default值,如果內(nèi)容錯(cuò)誤則拋出異常 */ public Integer getInteger(String key, Integer defaultValue) { String value = getValue(key); return value != null ? Integer.valueOf(value) : defaultValue; } /** * 取出Double類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null或內(nèi)容錯(cuò)誤則拋出異常. */ public Double getDouble(String key) { String value = getValue(key); if (value == null) { throw new NoSuchElementException(); } return Double.valueOf(value); } /** * 取出Double類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null則返回Default值,如果內(nèi)容錯(cuò)誤則拋出異常 */ public Double getDouble(String key, Integer defaultValue) { String value = getValue(key); return value != null ? Double.valueOf(value) : defaultValue.doubleValue(); } /** * 取出Boolean類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null拋出異常,如果內(nèi)容不是true/false則返回false. */ public Boolean getBoolean(String key) { String value = getValue(key); if (value == null) { throw new NoSuchElementException(); } return Boolean.valueOf(value); } /** * 取出Boolean類(lèi)型的Property,但以System的Property優(yōu)先.如果都為Null則返回Default值,如果內(nèi)容不為true/false則返回false. */ public Boolean getBoolean(String key, boolean defaultValue) { String value = getValue(key); return value != null ? Boolean.valueOf(value) : defaultValue; } /** * 載入多個(gè)文件, 文件路徑使用Spring Resource格式. */ private Properties loadProperties(String... resourcesPaths) { Properties props = new Properties(); for (String location : resourcesPaths) { InputStream is = null; try { Resource resource = resourceLoader.getResource(location); is = resource.getInputStream(); props.load(is); } catch (IOException ex) { logger.error("Could not load properties from path:" + location , ex); } finally { IOUtils.closeQuietly(is); } } return props; } }
Global.java 用來(lái)獲取全局的一些常量,可以是從配置文件中讀取的常量,也可以是定義成final static的常量,獲取配置文件的話是調(diào)用上面那個(gè)類(lèi)進(jìn)行獲取的。
package com.store.base.secondmodel.base; import java.io.File; import java.io.IOException; import java.util.Map; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.core.io.DefaultResourceLoader; import com.google.common.collect.Maps; import com.store.base.secondmodel.base.util.PropertiesLoader; import com.store.base.secondmodel.base.util.StringUtils; /** * 全局配置類(lèi) * @author yiyong_wu * */ public class Global { private static final Logger logger = LoggerFactory.getLogger(Global.class); /** * 當(dāng)前對(duì)象實(shí)例 */ private static Global global = new Global(); /** * 保存全局屬性值 */ private static Map<String, String> map = Maps.newHashMap(); /** * 屬性文件加載對(duì)象 */ private static PropertiesLoader loader = new PropertiesLoader("application.properties"); /** * 顯示/隱藏 public static final String SHOW = "1"; public static final String HIDE = "0"; /** * 是/否 */ public static final String YES = "1"; public static final String NO = "0"; /** * 狀態(tài) 上/下 app專(zhuān)用 */ public static final String UPSHVELF = "1"; public static final String DOWNSHVELF = "2"; public static final String SEPARATOR = "/"; /** * 對(duì)/錯(cuò) */ public static final String TRUE = "true"; public static final String FALSE = "false"; /** * 上傳文件基礎(chǔ)虛擬路徑 */ public static final String USERFILES_BASE_URL = "/userfiles/"; /** * 針對(duì)富文本編輯器,結(jié)尾會(huì)產(chǎn)生的空div */ public static final String ENDS = "<p><br></p>"; /** * 默認(rèn)空的私有構(gòu)造函數(shù) */ public Global() { //do nothing in this method,just empty } /** * 獲取當(dāng)前對(duì)象實(shí)例 */ public static Global getInstance() { return global; } /** * 獲取配置 */ public static String getConfig(String key) { String value = map.get(key); if (value == null){ value = loader.getProperty(key); map.put(key, value != null ? value : StringUtils.EMPTY); } return value; } /** * 獲取URL后綴 */ public static String getUrlSuffix() { return getConfig("urlSuffix"); } /** * 頁(yè)面獲取常量 * @see ${fns:getConst('YES')} */ public static Object getConst(String field) { try { return Global.class.getField(field).get(null); } catch (Exception e) { logger.error("獲取常量出錯(cuò)", e); } return null; } /** * 獲取工程路徑 * @return */ public static String getProjectPath(){ // 如果配置了工程路徑,則直接返回,否則自動(dòng)獲取。 String projectPath = Global.getConfig("projectPath"); if (StringUtils.isNotBlank(projectPath)){ return projectPath; } try { File file = new DefaultResourceLoader().getResource("").getFile(); if (file != null){ while(true){ File f = new File(file.getPath() + File.separator + "src" + File.separator + "main"); if (f == null || f.exists()){ break; } if (file.getParentFile() != null){ file = file.getParentFile(); }else{ break; } } projectPath = file.toString(); } } catch (IOException e) { logger.error("加載配置文件失敗", e); } return projectPath; } }
CookieUtil.java 從名稱(chēng)就知道是針對(duì)獲取和存儲(chǔ)cookie的一個(gè)工具類(lèi)
package com.store.base.secondmodel.base.util; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.net.URLEncoder; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * Cookie工具類(lèi) * @author yiyong_wu * */ public class CookieUtils { private static final Logger logger = LoggerFactory.getLogger(CookieUtils.class); /** * 私有構(gòu)造函數(shù) */ private CookieUtils() { } /** * 設(shè)置 Cookie(生成時(shí)間為1年) * @param name 名稱(chēng) * @param value 值 */ public static void setCookie(HttpServletResponse response, String name, String value) { setCookie(response, name, value, 60*60*24*365); } /** * 設(shè)置 Cookie * @param name 名稱(chēng) * @param value 值 * @param maxAge 生存時(shí)間(單位秒) * @param uri 路徑 */ public static void setCookie(HttpServletResponse response, String name, String value, String path) { setCookie(response, name, value, path, 60*60*24*365); } /** * 設(shè)置 Cookie * @param name 名稱(chēng) * @param value 值 * @param maxAge 生存時(shí)間(單位秒) * @param uri 路徑 */ public static void setCookie(HttpServletResponse response, String name, String value, int maxAge) { setCookie(response, name, value, "/", maxAge); } /** * 設(shè)置 Cookie * @param name 名稱(chēng) * @param value 值 * @param maxAge 生存時(shí)間(單位秒) * @param uri 路徑 */ public static void setCookie(HttpServletResponse response, String name, String value, String path, int maxAge) { Cookie cookie = new Cookie(name, null); cookie.setPath(path); cookie.setMaxAge(maxAge); try { cookie.setValue(URLEncoder.encode(value, "utf-8")); } catch (UnsupportedEncodingException e) { logger.error("不支持的編碼", e); } response.addCookie(cookie); } /** * 獲得指定Cookie的值 * @param name 名稱(chēng) * @return 值 */ public static String getCookie(HttpServletRequest request, String name) { return getCookie(request, null, name, false); } /** * 獲得指定Cookie的值,并刪除。 * @param name 名稱(chēng) * @return 值 */ public static String getCookie(HttpServletRequest request, HttpServletResponse response, String name) { return getCookie(request, response, name, true); } /** * 獲得指定Cookie的值 * @param request 請(qǐng)求對(duì)象 * @param response 響應(yīng)對(duì)象 * @param name 名字 * @param isRemove 是否移除 * @return 值 */ public static String getCookie(HttpServletRequest request, HttpServletResponse response, String name, boolean isRemove) { String value = null; Cookie[] cookies = request.getCookies(); if(cookies == null) { return value; } for (Cookie cookie : cookies) { if (cookie.getName().equals(name)) { try { value = URLDecoder.decode(cookie.getValue(), "utf-8"); } catch (UnsupportedEncodingException e) { logger.error("不支持的編碼", e); } if (isRemove) { cookie.setMaxAge(0); response.addCookie(cookie); } } } return value; } }
SpringContextHolder.java 主要是用來(lái)在java代碼中獲取當(dāng)前的ApplicationContext,需要在spring配置文件中配置這個(gè)bean并且懶加載設(shè)置成false;
package com.store.base.secondmodel.base.util; import org.apache.commons.lang3.Validate; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.beans.factory.DisposableBean; import org.springframework.context.ApplicationContext; import org.springframework.context.ApplicationContextAware; import org.springframework.context.annotation.Lazy; import org.springframework.stereotype.Service; @Service @Lazy(false) public class SpringContextHolder implements ApplicationContextAware, DisposableBean { private static Logger logger = LoggerFactory.getLogger(SpringContextHolder.class); private static ApplicationContext applicationContext = null; /** * 取得存儲(chǔ)在靜態(tài)變量中的ApplicationContext. */ public static ApplicationContext getApplicationContext() { assertContextInjected(); return applicationContext; } /** * 從靜態(tài)變量applicationContext中取得Bean, 自動(dòng)轉(zhuǎn)型為所賦值對(duì)象的類(lèi)型. */ @SuppressWarnings("unchecked") public static <T> T getBean(String name) { assertContextInjected(); return (T) applicationContext.getBean(name); } /** * 從靜態(tài)變量applicationContext中取得Bean, 自動(dòng)轉(zhuǎn)型為所賦值對(duì)象的類(lèi)型. */ public static <T> T getBean(Class<T> requiredType) { assertContextInjected(); return applicationContext.getBean(requiredType); } @Override public void destroy() throws Exception { SpringContextHolder.clearHolder(); } /** * 實(shí)現(xiàn)ApplicationContextAware接口, 注入Context到靜態(tài)變量中. */ @Override public void setApplicationContext(ApplicationContext applicationContext) { logger.debug("注入ApplicationContext到SpringContextHolder:{}", applicationContext); SpringContextHolder.applicationContext = applicationContext; if (SpringContextHolder.applicationContext != null) { logger.info("SpringContextHolder中的ApplicationContext被覆蓋, 原有ApplicationContext為:" + SpringContextHolder.applicationContext); } } /** * 清除SpringContextHolder中的ApplicationContext為Null. */ public static void clearHolder() { if (logger.isDebugEnabled()){ logger.debug("清除SpringContextHolder中的ApplicationContext:" + applicationContext); } applicationContext = null; } /** * 檢查ApplicationContext不為空. */ private static void assertContextInjected() { Validate.validState(applicationContext != null, "applicaitonContext屬性未注入, 請(qǐng)?jiān)赼pplicationContext.xml中定義SpringContextHolder."); } }
StringUtils.java字符串相關(guān)的一個(gè)工具類(lèi)
package com.store.base.secondmodel.base.util; import java.io.UnsupportedEncodingException; import java.util.Locale; import java.util.regex.Matcher; import java.util.regex.Pattern; import javax.servlet.http.HttpServletRequest; import org.apache.commons.lang3.StringEscapeUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; import org.springframework.web.servlet.LocaleResolver; import com.store.base.util.Encodes; /** * 字符串幫助類(lèi) * @author yiyong_wu * */ public class StringUtils extends org.apache.commons.lang3.StringUtils { private static final char SEPARATOR = '_'; private static final String CHARSET_NAME = "UTF-8"; private static final Logger logger = LoggerFactory.getLogger(StringUtils.class); /** * 轉(zhuǎn)換為字節(jié)數(shù)組 * @param str * @return */ public static byte[] getBytes(String str){ if (str != null){ try { return str.getBytes(CHARSET_NAME); } catch (UnsupportedEncodingException e) { logger.error("", e); return new byte[0]; } }else{ return new byte[0]; } } /** * 轉(zhuǎn)換為字節(jié)數(shù)組 * @param str * @return */ public static String toString(byte[] bytes){ try { return new String(bytes, CHARSET_NAME); } catch (UnsupportedEncodingException e) { logger.error("", e); return EMPTY; } } /** * 是否包含字符串 * @param str 驗(yàn)證字符串 * @param strs 字符串組 * @return 包含返回true */ public static boolean inString(String str, String... strs){ if (str != null){ for (String s : strs){ if (str.equals(trim(s))){ return true; } } } return false; } /** * 替換掉HTML標(biāo)簽方法 */ public static String replaceHtml(String html) { if (isBlank(html)){ return ""; } String regEx = "<.+?>"; Pattern p = Pattern.compile(regEx); Matcher m = p.matcher(html); return m.replaceAll(""); } /** * 替換為手機(jī)識(shí)別的HTML,去掉樣式及屬性,保留回車(chē)。 * @param html * @return */ public static String replaceMobileHtml(String html){ if (html == null){ return ""; } return html.replaceAll("<([a-z]+?)\\s+?.*?>", "<$1>"); } /** * 替換為手機(jī)識(shí)別的HTML,去掉樣式及屬性,保留回車(chē)。 * @param txt * @return */ public static String toHtml(String txt){ if (txt == null){ return ""; } return replace(replace(Encodes.escapeHtml(txt), "\n", "<br/>"), "\t", " "); } /** * 縮略字符串(不區(qū)分中英文字符) * @param str 目標(biāo)字符串 * @param length 截取長(zhǎng)度 * @return */ public static String abbr(String str, int length) { if (str == null) { return ""; } try { StringBuilder sb = new StringBuilder(); int currentLength = 0; for (char c : replaceHtml(StringEscapeUtils.unescapeHtml4(str)).toCharArray()) { currentLength += String.valueOf(c).getBytes("GBK").length; if (currentLength <= length - 3) { sb.append(c); } else { sb.append("..."); break; } } return sb.toString(); } catch (UnsupportedEncodingException e) { logger.error("", e); } return ""; } /** * 轉(zhuǎn)換為Double類(lèi)型 */ public static Double toDouble(Object val){ if (val == null){ return 0D; } try { return Double.valueOf(trim(val.toString())); } catch (Exception e) { logger.error("", e); return 0D; } } /** * 轉(zhuǎn)換為Float類(lèi)型 */ public static Float toFloat(Object val){ return toDouble(val).floatValue(); } /** * 轉(zhuǎn)換為L(zhǎng)ong類(lèi)型 */ public static Long toLong(Object val){ return toDouble(val).longValue(); } /** * 轉(zhuǎn)換為Integer類(lèi)型 */ public static Integer toInteger(Object val){ return toLong(val).intValue(); } /** * 獲得i18n字符串 */ public static String getMessage(String code, Object[] args) { LocaleResolver localLocaleResolver = SpringContextHolder.getBean(LocaleResolver.class); HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest(); Locale localLocale = localLocaleResolver.resolveLocale(request); return SpringContextHolder.getApplicationContext().getMessage(code, args, localLocale); } /** * 獲得用戶(hù)遠(yuǎn)程地址 */ public static String getRemoteAddr(HttpServletRequest request){ String remoteAddr = request.getHeader("X-Real-IP"); if (isNotBlank(remoteAddr)) { remoteAddr = request.getHeader("X-Forwarded-For"); } if (isNotBlank(remoteAddr)) { remoteAddr = request.getHeader("Proxy-Client-IP"); } if (isNotBlank(remoteAddr)) { remoteAddr = request.getHeader("WL-Proxy-Client-IP"); } return remoteAddr != null ? remoteAddr : request.getRemoteAddr(); } /** * 駝峰命名法工具 * @return * toCamelCase("hello_world") == "helloWorld" * toCapitalizeCamelCase("hello_world") == "HelloWorld" * toUnderScoreCase("helloWorld") = "hello_world" */ public static String toCamelCase(String s) { String s1 =s; if (s1 == null) { return null; } s1 = s.toLowerCase(); StringBuilder sb = new StringBuilder(s1.length()); boolean upperCase = false; for (int i = 0; i < s1.length(); i++) { char c = s1.charAt(i); if (c == SEPARATOR) { upperCase = true; } else if (upperCase) { sb.append(Character.toUpperCase(c)); upperCase = false; } else { sb.append(c); } } return sb.toString(); } /** * 駝峰命名法工具 * @return * toCamelCase("hello_world") == "helloWorld" * toCapitalizeCamelCase("hello_world") == "HelloWorld" * toUnderScoreCase("helloWorld") = "hello_world" */ public static String toCapitalizeCamelCase(String s) { String s1 = s; if (s1 == null) { return null; } s1 = toCamelCase(s1); return s1.substring(0, 1).toUpperCase() + s1.substring(1); } /** * 駝峰命名法工具 * @return * toCamelCase("hello_world") == "helloWorld" * toCapitalizeCamelCase("hello_world") == "HelloWorld" * toUnderScoreCase("helloWorld") = "hello_world" */ public static String toUnderScoreCase(String s) { if (s == null) { return null; } StringBuilder sb = new StringBuilder(); boolean upperCase = false; for (int i = 0; i < s.length(); i++) { char c = s.charAt(i); boolean nextUpperCase = true; if (i < (s.length() - 1)) { nextUpperCase = Character.isUpperCase(s.charAt(i + 1)); } if ((i > 0) && Character.isUpperCase(c)) { if (!upperCase || !nextUpperCase) { sb.append(SEPARATOR); } upperCase = true; } else { upperCase = false; } sb.append(Character.toLowerCase(c)); } return sb.toString(); } /** * 轉(zhuǎn)換為JS獲取對(duì)象值,生成三目運(yùn)算返回結(jié)果 * @param objectString 對(duì)象串 * 例如:row.user.id * 返回:!row?'':!row.user?'':!row.user.id?'':row.user.id */ public static String jsGetVal(String objectString){ StringBuilder result = new StringBuilder(); StringBuilder val = new StringBuilder(); String[] vals = split(objectString, "."); for (int i=0; i<vals.length; i++){ val.append("." + vals[i]); result.append("!"+(val.substring(1))+"?'':"); } result.append(val.substring(1)); return result.toString(); } }
有了上面這些基礎(chǔ)的東西,只需要在寫(xiě)一個(gè)控制層接口,就可以看到每次返回一個(gè)page對(duì)象,然后里面封裝好了查詢(xún)對(duì)象的列表,并且是按分頁(yè)得出列表。
package com.store.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.bind.annotation.RestController; import com.store.base.secondmodel.base.Page; import com.store.base.secondmodel.pratice.model.Product; import com.store.base.secondmodel.pratice.service.ProductService; /** *TODO *2016年10月11日 *yiyong_wu */ @RestController @RequestMapping("/product") public class ProductController { @Autowired private ProductService productService; @ResponseBody @RequestMapping(value="/getPageProduct") public Page<Product> getPageProduct(HttpServletRequest request,HttpServletResponse response){ Page<Product> page = productService.findPage(new Page<Product>(request,response), new Product()); return page; } }
最后在看一下頁(yè)面怎么使用這個(gè)page對(duì)象,這樣我們就完整地介紹了這個(gè)一個(gè)分頁(yè)功能,代碼很多,但很完整。
<%@ page contentType="text/html;charset=UTF-8"%> <%@ include file="/WEB-INF/views/include/taglib.jsp"%> <html> <head> <title></title> <meta name="decorator" content="default" /> function page(n, s) { if (n) $("#pageNo").val(n); if (s) $("#pageSize").val(s); $("#searchForm").attr("action", "${ctx}/app/bank/list"); $("#searchForm").submit(); return false; } </script> </head> <body> <form:form id="searchForm" modelAttribute="XXXX" action="${ctx}/XXX" method="post" class="breadcrumb form-search "> <input id="pageNo" name="pageNo" type="hidden" value="${page.pageNo}" /> <input id="pageSize" name="pageSize" type="hidden" value="${page.pageSize}" /> <ul class="ul-form"> <li> <label>是否上架:</label> <form:select id="status" path="status" class="input-medium"> <form:option value="" label=""/> <form:options items="${fns:getDictList('yes_no_app')}" itemLabel="label" itemValue="value" htmlEscape="false"/> </form:select> </li> <li class="btns"><input id="btnSubmit" class="btn btn-primary" type="submit" value="查詢(xún)"/> <li class="clearfix"></li> </ul> </form:form> <sys:message content="${message}" /> <sys:message content="${message}" /> <table id="contentTable" class="table table-striped table-bordered table-condensed"> <thead> <tr> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> <th>XXXX</th> </tr> </thead> <tbody> <c:forEach items="${page.list}" var="XXXX"> <tr> <td>${XXXX.name}</td> <td><a href="${ctx}/app/bank/form?id=${XXXX.id}">${XXXX.}</a></td> <td>${XXXX.}</td> <td>${XXXX.}</td> <td>${XXXX.}</td> <td>${fns:getDictLabel(XXXX.isHot, 'yes_no_app', '無(wú)')}</td> <td>${XXXX.}</td> <td><c:if test="${XXXX.status==1 }">上架</c:if> <c:if test="${XXXX.status==2 }">下架</c:if> </td> </tr> </c:forEach> </tbody> </table> <div class="pagination">${page} <li style="padding-top: 6px;padding-left: 12px;float: left;">共${page.count}條</li></div> </body> </html>
到這里就基本上把整個(gè)分頁(yè)功能描述得比較清楚了,希望可以幫助到你們快速解決分頁(yè)這個(gè)問(wèn)題,當(dāng)然要在前端顯示分頁(yè)漂亮的話要針對(duì)li做一些css樣式啥的,最后祝福你可以快速掌握這個(gè)分頁(yè)功能!
以上所述是小編給大家介紹的Mybatis常用分頁(yè)插件實(shí)現(xiàn)快速分頁(yè)處理技巧,希望對(duì)大家有所幫助,如果大家有任何疑問(wèn)請(qǐng)給我留言,小編會(huì)及時(shí)回復(fù)大家的。在此也非常感謝大家對(duì)腳本之家網(wǎng)站的支持!
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- 詳解MyBatis自定義Plugin插件
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- mybatis分頁(yè)插件pageHelper詳解及簡(jiǎn)單實(shí)例
- Mybatis分頁(yè)插件PageHelper的使用詳解
- 自己動(dòng)手寫(xiě)的mybatis分頁(yè)插件(極其簡(jiǎn)單好用)
- Java簡(jiǎn)單實(shí)現(xiàn)SpringMVC+MyBatis分頁(yè)插件
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