import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
public class BeanUtils {
@SuppressWarnings("unchecked")
public static void copyProperties(Object target,Object source) throws Exception{
/*分别获得源对象和目标对象的Class类型对象,Class对象是整个反射机制的源头和灵魂!
Class对象是在类加载的时候产生,保存着类的相关属性,构造器,方法等信息
*/
Class sourceClz = source.getClass();
Class targetClz = target.getClass();
//得到Class对象所表征的类的所有属性(包括私有属性)
Field[] fields = sourceClz.getDeclaredFields();
for (int i = 0; i < fields.length; i++) {
String fieldName = fields[i].getName();
Field targetField = null;
try {
//得到targetClz对象所表征的类的名为fieldName的属性,不存在就进入下次循环
targetField = targetClz.getDeclaredField(fieldName);
} catch (Exception e) {
e.printStackTrace();
break;
}
//判断sourceClz字段类型和targetClz同名字段类型是否相同
if(fields[i].getType()==targetField.getType()){
//由属性名字得到对应get和set方法的名字
String getMethodName = "get"+fieldName.substring(0,1).toUpperCase()+fieldName.substring(1);
String setMethodName = "set"+fieldName.substring(0,1).toUpperCase()+fieldName.substring(1);
//由方法的名字得到get和set方法的Method对象
Method getMethod;
try {
getMethod = sourceClz.getDeclaredMethod(getMethodName, new Class[]{});
Method setMethod = targetClz.getDeclaredMethod(setMethodName, fields[i].getType());
//调用source对象的getMethod方法
Object result = getMethod.invoke(source, new Object[]{});
//调用target对象的setMethod方法
setMethod.invoke(target, result);
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}else{
throw new Exception("同名属性类型不匹配!");
}
}
}
}
以上是同名属性类型相同的对象拷贝,要想字段名字改变的拷贝可以用如下方法:
public class BeanUtils {
public static void copyProperties(Object target,Object source) throws Exception{
Class sourceClz = source.getClass();
Class targetClz = target.getClass();
Field[] fields = sourceClz.getDeclaredFields();
Field[] targets = targetClz.getDeclaredFields();
for (int i = 0; i < targets.length; i++) {
String fieldName = fields[i].getName();
String targetName = targets[i].getName();
if(fields[i].getType()==targets[i].getType()){
String getMethodName = "get"+fieldName.substring(0,1).toUpperCase()+fieldName.substring(1);
String setMethodName = "set"+targetName.substring(0,1).toUpperCase()+targetName.substring(1);
Method getMethod;
try {
getMethod = sourceClz.getDeclaredMethod(getMethodName, new Class[]{});
Method setMethod = targetClz.getDeclaredMethod(setMethodName, fields[i].getType());
Object result = getMethod.invoke(source, new Object[]{});
setMethod.invoke(target, result);
} catch (Exception e) {
e.printStackTrace();
}
}else{
throw new Exception("属性类型不匹配!");
}
}
}
}