public class UpdateUtil {
    /**
     * 所有為空值的屬性都不copy
     *
     * @param source
     * @param target
     */
    public static void copyNullProperties(Object source, Object target) {
        BeanUtils.copyProperties(source, target, getNullField(source));
    }
    /**
     * 獲取屬性中為空的字段
     *
     * @param target
     * @return
     */
    private static String[] getNullField(Object target) {
        BeanWrapper beanWrapper = new BeanWrapperImpl(target);
        PropertyDescriptor[] propertyDescriptors = beanWrapper.getPropertyDescriptors();
        Set<String> notNullFieldSet = new HashSet<>();
        if (propertyDescriptors.length > 0) {
            for (PropertyDescriptor p : propertyDescriptors) {
                String name = p.getName();
                Object value = beanWrapper.getPropertyValue(name);
                if (Objects.isNull(value)) {
                    notNullFieldSet.add(name);
                }
            }
        }
        String[] notNullField = new String[notNullFieldSet.size()];
        return notNullFieldSet.toArray(notNullField);
    }
    public static void main(String[] args) {
        TopMenuConfigEntity topMenuConfigEntity1 = new TopMenuConfigEntity();
        topMenuConfigEntity1.setWardCode("cat");
        topMenuConfigEntity1.setTitle("animal");
        TopMenuConfigEntity topMenuConfigEntity2 = new TopMenuConfigEntity();
        topMenuConfigEntity2.setWardCode("dog");
        UpdateUtil.copyNullProperties(topMenuConfigEntity2,topMenuConfigEntity1);
        System.out.println(topMenuConfigEntity1.getTitle());
    }
}

public static void copyProperties(Object source, Object target, String... ignoreProperties) throws BeansException {
?? ??? ?copyProperties(source, target, null, ignoreProperties);
?? ?}

 public static void main(String[] args) {
        TopMenuConfigEntity topMenuConfigEntity1 = new TopMenuConfigEntity();
        topMenuConfigEntity1.setWardCode("cat");
        topMenuConfigEntity1.setTitle("animal");
        topMenuConfigEntity1.setCreateTime(new Date());
        TopMenuConfigEntity topMenuConfigEntity2 = new TopMenuConfigEntity();
        String[] ignoreArray = new String[]{"title","createTime"};
        BeanUtils.copyProperties(topMenuConfigEntity2,topMenuConfigEntity1,ignoreArray);
        System.out.println("title : "+topMenuConfigEntity2.getTitle() +";createTime :" + topMenuConfigEntity2.getCreateTime());
    }

public static void copyProperties(Object source, Object target) throws BeansException {
        copyProperties(source, target, (Class)null, (String[])null);
    }
 
public static void copyProperties(Object source, Object target, Class<?> editable) throws BeansException {
        copyProperties(source, target, editable, (String[])null);
    }
 
public static void copyProperties(Object source, Object target, String... ignoreProperties) throws BeansException {
        copyProperties(source, target, (Class)null, ignoreProperties);
    }
 
private static void copyProperties(Object source, Object target, Class<?> editable, String... ignoreProperties) throws BeansException {
        Assert.notNull(source, "Source must not be null");
        Assert.notNull(target, "Target must not be null");
        Class<?> actualEditable = target.getClass();
        if(editable != null) {
            if(!editable.isInstance(target)) {
                throw new IllegalArgumentException("Target class [" + target.getClass().getName() + "] not assignable to Editable class [" + editable.getName() + "]");
            }
 
            actualEditable = editable;
        }
 
        PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);
        List<String> ignoreList = ignoreProperties != null?Arrays.asList(ignoreProperties):null;
        PropertyDescriptor[] var7 = targetPds;
        int var8 = targetPds.length;
 
        for(int var9 = 0; var9 < var8; ++var9) {
            PropertyDescriptor targetPd = var7[var9];
            Method writeMethod = targetPd.getWriteMethod();
            if(writeMethod != null && (ignoreList == null || !ignoreList.contains(targetPd.getName()))) {
                PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(), targetPd.getName());
                if(sourcePd != null) {
                    Method readMethod = sourcePd.getReadMethod();
                    if(readMethod != null && ClassUtils.isAssignable(writeMethod.getParameterTypes()[0], readMethod.getReturnType())) {
                        try {
                            if(!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {
                                readMethod.setAccessible(true);
                            }
 
                            Object value = readMethod.invoke(source, new Object[0]);
                            if(!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers())) {
                                writeMethod.setAccessible(true);
                            }
 
                            writeMethod.invoke(target, new Object[]{value});
                        } catch (Throwable var15) {
                            throw new FatalBeanException("Could not copy property '" + targetPd.getName() + "' from source to target", var15);
                        }
                    }
                }
            }
        }
 
    }

* java.lang.BigDecimal   
  
* java.lang.BigInteger   
  
* boolean and java.lang.Boolean   
  
* byte and java.lang.Byte   
  
* char and java.lang.Character   
  
* java.lang.Class   
  
* double and java.lang.Double   
  
* float and java.lang.Float   
  
* int and java.lang.Integer   
  
* long and java.lang.Long   
  
* short and java.lang.Short   
  
* java.lang.String   
  
* java.sql.Date   
  
* java.sql.Time   
  
* java.sql.Timestamp

import org.springframework.beans.BeanUtils;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware; 
import java.util.HashSet;
import java.util.Set; 

public class SpringUtil implements ApplicationContextAware {
 
    /** 
     * 當前IOC 
     *  
     */  
    private static ApplicationContext applicationContext;  
 
    /** 
     * * 設(shè)置當前上下文環(huán)境，此方法由spring自動裝配 
     *  
     */  
    @Override  
    public void setApplicationContext(ApplicationContext arg0)  
            throws BeansException {  
        applicationContext = arg0;  
    }  
 
    /** 
     * 從當前IOC獲取bean 
     * 
     * @param id 
     * bean的id 
     * @return 
     *
     */  
    public static Object getObject(String id) {  
        Object object = null;  
        object = applicationContext.getBean(id);  
        return object;  
    } 
    
    public static String[] getNullPropertyNames (Object source) {
        final BeanWrapper src = new BeanWrapperImpl(source);
        java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();
 
        Set<String> emptyNames = new HashSet<String>();
        for(java.beans.PropertyDescriptor pd : pds) {
            Object srcValue = src.getPropertyValue(pd.getName());
            if (srcValue == null) emptyNames.add(pd.getName());
        }
        String[] result = new String[emptyNames.size()];
        return emptyNames.toArray(result);
    }
 
    public static void copyPropertiesIgnoreNull(Object src, Object target){
        BeanUtils.copyProperties(src, target, getNullPropertyNames(src));
    } 
}

public class TestBeanUtiles {
? ? public static void main(String[] args) {
? ? ? ? NewPerson newPerson = new NewPerson();
? ? ? ? newPerson.setName("bifuguo");//前臺用戶更新過的數(shù)據(jù)，例如前臺只修改了用戶名
? ? ? ? //下面我們假設(shè)是從數(shù)據(jù)庫加載出來的老數(shù)據(jù)
? ? ? ? OldPerson oldPerson = new OldPerson();
? ? ? ? oldPerson.setSex("nv");
? ? ? ? oldPerson.setAge(5);
? ? ? ? //如果我們想把新數(shù)據(jù)更新到老數(shù)據(jù)這個對象里面，我們就可以借助BeanUtils.copyProperties()的方法如下：
? ? ? ? //BeanUtils.copyProperties(newPerson, oldPerson);
? ? ? ? SpringUtil.copyPropertiesIgnoreNull(newPerson, oldPerson);
? ? ? ? System.out.println(newPerson.toString());
? ? ? ? System.out.println(oldPerson.toString());
? ? }
}