JavaWeb應(yīng)用實(shí)例:用servlet實(shí)現(xiàn)oracle 基本增刪改查
很久沒有寫博客了,可能是太懶散,不愿意把時間花在這上面,可是我心里還是知道寫博客的重要性的 ,所以從今天開始 ,我將與大家分享一下我學(xué)Java WEB寫的一些小實(shí)例 ,我個人是不太喜歡書本上的晦澀的概念的,所以我花了更多的時間在一些應(yīng)用實(shí)例上,我覺得這樣的學(xué)習(xí)方式很適合我,由簡到繁,由淺入深
廢話不多話,開始我們的第一個實(shí)例:
servlet實(shí)現(xiàn)Oracle 基本增刪改查
開發(fā)環(huán)境:JDK7 +Myeclipse10+tomcat7.0+oracle 11g
首先附上數(shù)據(jù)庫創(chuàng)建腳本:
create table student( id VARCHAR2(50) PRIMARY KEY NOT NULL, name varchar2(50) NOT NULL, calssGrent varchar2(50) NOT NULL , result varchar(12) NOT NULL ); insert into student(id,name,calssGrent,result) values(perseq.nextval,'張三','33','98')
下圖為代碼結(jié)構(gòu)圖和功能演示界面做的比較糟糕 只為實(shí)現(xiàn)功能:

MMC_01.Java
頁面 //主界面提供添加,修改刪除的方法

package org.lsy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import oracle.jdbc.oracore.TDSPatch;
public class MMC_01 extends HttpServlet
{
// 驅(qū)動程序就是之前在classpath中配置的jdbc的驅(qū)動程序的jar包中
// 連接地址是由各個數(shù)據(jù)庫生產(chǎn)商單獨(dú)提供的,所以需要單獨(dú)記住
public static final String DBURL = "jdbc:oracle:thin:@localhost:1521:LIUSY";
// 連接數(shù)據(jù)庫的用戶名
public static final String DBUSER = "scott";
// 連接數(shù)據(jù)庫的密碼
public static final String DBPASS = "tiger";
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
//設(shè)置請求和響應(yīng)的編碼 ,不然頁面上容易出現(xiàn)亂碼
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;UTF-8");
//輸出流
PrintWriter out = response.getWriter();
//數(shù)據(jù)庫連接代碼
try
{
Connection conn = null; // 表示數(shù)據(jù)庫的連接的對象
Statement stmt = null; // 表示數(shù)據(jù)庫的更新操作
String sql="insert into student(id,name,calssGrent,result) values('67','劉12宇','33','98')";
System.out.println(sql) ;
// 1、使用Class類加載驅(qū)動程序
Class.forName("oracle.jdbc.driver.OracleDriver");
// 2、連接數(shù)據(jù)庫
conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
// 3、Statement接口需要通過Connection接口進(jìn)行實(shí)例化操作
stmt = conn.createStatement();
//用 rs獲取查詢結(jié)果 ,這里的SQL語句最好不要用* 我的字段比較少所以就偷一下懶,-,-
ResultSet rs=stmt.executeQuery("select *from student");
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
//輸出表頭部分
out.print("<table align='center' border='1'><tr><td>姓名" +
"</td><td>班級</td><td>成績</td><td>修改</td><td>刪除</td></tr>");
while(rs.next())
{
//獲取數(shù)據(jù)庫中的ID
String id=rs.getString("id");
//輸出一列元素
out.print("<tr><td>"+rs.getString("name")
+"</td><td>"+rs.getString("calssGrent")+"" +
"</td><td>"+rs.getString("result")+"</td>" +
"<td><a href='UpdatePage?id="+id+"'>修改</a></td>" +
"<td><a href='delete?id="+id+"'> 刪除 </a></td></tr>");
}
out.println("<td><a href=AddPage>添加數(shù)據(jù)</a></td>");
out.println(" </BODY>");
out.println("</HTML>");
conn.close();
}
catch (Exception e)
{
e.printStackTrace();
}
out.flush();
out.close();
}
}
UpdatePage.java //獲取要修改的數(shù)據(jù) ,并把修改過的數(shù)據(jù)提交給Update
package org.lsy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.sun.crypto.provider.RSACipher;
public class UpdatePage extends HttpServlet
{
// 連接地址是由各個數(shù)據(jù)庫生產(chǎn)商單獨(dú)提供的,所以需要單獨(dú)記住
public static final String DBURL = "jdbc:oracle:thin:@localhost:1521:LIUSY";
// 連接數(shù)據(jù)庫的用戶名
public static final String DBUSER = "scott";
// 連接數(shù)據(jù)庫的密碼
public static final String DBPASS = "tiger";
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
String id=request.getParameter("id");
//設(shè)置請求和響應(yīng)的編碼 ,不然頁面上容易出現(xiàn)亂碼
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;UTF-8");
PrintWriter out = response.getWriter();
try
{
Connection conn = null; // 表示數(shù)據(jù)庫的連接的對象
Statement stmt = null; // 表示數(shù)據(jù)庫的更新操作
// 1、使用Class類加載驅(qū)動程序
Class.forName("oracle.jdbc.driver.OracleDriver");
// 2、連接數(shù)據(jù)庫
conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
// 3、Statement接口需要通過Connection接口進(jìn)行實(shí)例化操作
stmt = conn.createStatement();
//用 rs獲取查詢結(jié)果 ,這里的SQL語句最好不要用* 我的字段比較少所以就偷一下懶,-,-
ResultSet rs=stmt.executeQuery("select *from student where id='"+id+"'");
while (rs.next())
{
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
//輸入成績的表單,提交至Update
out.print(" <form action='Update' method='post'> ");
out.print("<table align='center'> <tr><td>姓名:<input type='text' value='"+rs.getString("name")+"'
name='name' size=20 ></td></tr>");
out.print("<tr><td>班級:<input type='text' value='"+rs.getString("calssGrent")+"' name='grent' size=20></td></tr>");
out.print("<tr><td>成績:<input type='text' value='"+rs.getString("result")+"' name='result' size=20></td></tr>");
//為了作為查詢數(shù)據(jù)庫的條件 ,這里要把ID傳過去
out.print("<input type='hidden' value='"+id+"' name='id'>");
out.print("<tr><td><input type='submit' value='修改'><input type='reset' value='重置'></td></tr></table></form>");
out.print(" </BODY>");
out.println("</HTML>");
}
out.flush();
out.close();
}
catch (Exception e) {
e.printStackTrace();// TODO: handle exception
}
}
}
Update.java 接收要修改的數(shù)據(jù) ,并更新數(shù)據(jù)庫
package org.lsy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Update extends HttpServlet
{
// 驅(qū)動程序就是之前在classpath中配置的jdbc的驅(qū)動程序的jar包中
// 連接地址是由各個數(shù)據(jù)庫生產(chǎn)商單獨(dú)提供的,所以需要單獨(dú)記住
public static final String DBURL = "jdbc:oracle:thin:@localhost:1521:LIUSY";
// 連接數(shù)據(jù)庫的用戶名
public static final String DBUSER = "scott";
// 連接數(shù)據(jù)庫的密碼
public static final String DBPASS = "tiger";
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
try
{
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;UTF-8");
PrintWriter out = response.getWriter();
Connection conn = null; // 表示數(shù)據(jù)庫的連接的對象
Statement stmt = null; // 表示數(shù)據(jù)庫的更新操作
//獲取表單提交的參數(shù)
String id=request.getParameter("id");
System.out.println(id);
String name=request.getParameter("name");
String grent=request.getParameter("grent");
String result=request.getParameter("result");
//更新SQL
String sqlString="update student set name='"+name+"' ," +
"calssGrent='"+grent+"',result='"+result+"' where id='"+id+"' ";
// 1、使用Class類加載驅(qū)動程序
Class.forName("oracle.jdbc.driver.OracleDriver");
// 2、連接數(shù)據(jù)庫
conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
// 3、Statement接口需要通過Connection接口進(jìn)行實(shí)例化操作
stmt = conn.createStatement();
int pd=stmt.executeUpdate(sqlString);
if(pd!=0)
{
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" 更新成功<br><a href=MMC_01>查看列表</a> ");
out.println(" </BODY>");
out.println("</HTML>");
}
out.flush();
out.close();
stmt.close();
conn.close();
}
catch (Exception e)
{
// TODO: handle exception
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
doGet(request, response);
}
}
addPage .java,添加數(shù)據(jù)頁面
package org.lsy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class AddPage extends HttpServlet
{
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
//設(shè)置請求和響應(yīng)的編碼 ,不然頁面上容易出現(xiàn)亂碼
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;UTF-8");
PrintWriter out = response.getWriter();
out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
out.println("<HTML>");
out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");
out.println(" <BODY>");
//輸入成績的表單,提交至add
out.print(" <form action='Add' method='post'> ");
out.print("<table align='center'> <tr><td>姓名:<input type='text' name='name' size=20 ></td></tr>");
out.print("<tr><td>班級:<input type='text' name='grent' size=20></td></tr>");
out.print("<tr><td>成績:<input type='text' name='result' size=20></td></tr>");
out.print("<tr><td><input type='submit' value='添加'><input type='reset' value='重置'></td></tr></table></form>");
out.println("<tr><td><a href=MMC_01>查看列表</a></td></tr>");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
}
add 接收addpage傳來的傳,更新數(shù)據(jù)庫
package org.lsy.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.sun.org.apache.xerces.internal.impl.io.UTF8Reader;
import oracle.jdbc.oracore.TDSPatch;
public class Add extends HttpServlet
{
// 驅(qū)動程序就是之前在classpath中配置的jdbc的驅(qū)動程序的jar包中
// 連接地址是由各個數(shù)據(jù)庫生產(chǎn)商單獨(dú)提供的,所以需要單獨(dú)記住
public static final String DBURL = "jdbc:oracle:thin:@localhost:1521:LIUSY";
// 連接數(shù)據(jù)庫的用戶名
public static final String DBUSER = "scott";
// 連接數(shù)據(jù)庫的密碼
public static final String DBPASS = "tiger";
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException
{
// TODO Auto-generated method stub
doGet(req, resp);
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException
{
//設(shè)置請求和響應(yīng)的編碼 ,不然頁面上容易出現(xiàn)亂碼
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
response.setContentType("text/html;UTF-8");
//輸出流
PrintWriter out = response.getWriter();
//數(shù)據(jù)庫連接代碼
try
{
Connection conn = null; // 表示數(shù)據(jù)庫的連接的對象
Statement pstmt = null; // 表示數(shù)據(jù)庫的更新操作
String nameString=request.getParameter("name");
String grentString=request.getParameter("grent");
String resultString=request.getParameter("result");
System.out.print(nameString);
String sql="insert into student(id,name,calssGrent,result)
values(perseq.nextval,'"+nameString+"','"+grentString+"','"+resultString+"')";
// 1、使用Class類加載驅(qū)動程序
Class.forName("oracle.jdbc.driver.OracleDriver");
// 2、連接數(shù)據(jù)庫
conn = DriverManager.getConnection(DBURL, DBUSER, DBPASS);
pstmt=conn.createStatement();
int pd=pstmt.executeUpdate(sql);
if (pd!=0)
{
out.println("添加成功");
out.println("<br><a href=MMC_01>查看列表</a>");
}
conn.close();
}
catch (Exception e)
{
e.printStackTrace();
}
out.flush();
out.close();
}
}
web.xml 配置文件
<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <display-name></display-name> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <servlet-name>MMC_01</servlet-name> <servlet-class>org.lsy.servlet.MMC_01</servlet-class> </servlet> <servlet> <servlet-name>delete</servlet-name> <servlet-class>org.lsy.servlet.delete</servlet-class> </servlet> <servlet> <servlet-name>Add</servlet-name> <servlet-class>org.lsy.servlet.Add</servlet-class> </servlet> <servlet> <servlet-name>AddPage</servlet-name> <servlet-class>org.lsy.servlet.AddPage</servlet-class> </servlet> <servlet> <servlet-name>UpdatePage</servlet-name> <servlet-class>org.lsy.servlet.UpdatePage</servlet-class> </servlet> <servlet> <servlet-name>Update</servlet-name> <servlet-class>org.lsy.servlet.Update</servlet-class> </servlet> <servlet-mapping> <servlet-name>MMC_01</servlet-name> <url-pattern>/MMC_01</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>delete</servlet-name> <url-pattern>/delete</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>Add</servlet-name> <url-pattern>/Add</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>AddPage</servlet-name> <url-pattern>/AddPage</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>UpdatePage</servlet-name> <url-pattern>/UpdatePage</url-pattern> </servlet-mapping> <servlet-mapping> <servlet-name>Update</servlet-name> <url-pattern>/Update</url-pattern> </servlet-mapping> </web-app>
本人并非老鳥,一直處于學(xué)習(xí)中,有什么錯誤的地方還請指證,上面的代碼有很多重復(fù)的部分,很多不合理的地方 ,比較數(shù)據(jù)庫連接直接暴露于操作servlet中 ,為了看的更直觀 ,我就沒有更改……
以上就是本文的全部內(nèi)容,希望對大家的學(xué)習(xí)有所幫助,也希望大家多多支持腳本之家。
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