本文目录一览：

1. Java中，复制一个对象，有什么好的方法
2. java怎么样构造函数复制一个对象
3. 如何复制一个java对象

Java中，复制一个对象，有什么好的方法

使用Java的反射机制实现：为了能更好的区分，写成了两个类，可以运行下面的代码看看效果

import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class Test {
    public static void main(String[] args) throws Exception {
        Customer1 c1 = new Customer1();
        c1.setName("c1");
        List<String> list = new ArrayList<String>();
        list.add("1");
        list.add("2");
        c1.setList(list);
        Map<String, String> map = new HashMap<String, String>();
        map.put("map1", "map1");
        map.put("map2", "map2");
        c1.setMap(map);
        Customer2 c2 = new Customer2();
        Class c = c1.getClass();
        Class class2 = c2.getClass();
        Field fields[] = c.getDeclaredFields();
        for (int i = 0; i < fields.length; i++) {
            Field field = fields[i];
            String fieldName = field.getName();
            String firstLetter = fieldName.substring(0, 1).toUpperCase();
            String getMethodName = "get" + firstLetter + fieldName.substring(1);
            String setMethodName = "set" + firstLetter + fieldName.substring(1);
            Method getMethod = c.getMethod(getMethodName, new Class[] {});
            Method setMethod = class2.getMethod(setMethodName, new Class[] { field.getType() });
            Object value = getMethod.invoke(c1, new Object[] {});
            setMethod.invoke(c2, new Object[] { value });
        }
        System.out.println(c2.getName());
        System.out.println(c2.getList());
        System.out.println(c2.getMap());
    }
}
class Customer1 {
    private String name;
    private List<String> list;
    private Map<String, String> map;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public List<String> getList() {
        return list;
    }
    public void setList(List<String> list) {
        this.list = list;
    }
    public Map<String, String> getMap() {
        return map;
    }
    public void setMap(Map<String, String> map) {
        this.map = map;
    }
}
class Customer2 {
    private String name;
    private List<String> list;
    private Map<String, String> map;
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public List<String> getList() {
        return list;
    }
    public void setList(List<String> list) {
        this.list = list;
    }
    public Map<String, String> getMap() {
        return map;
    }
    public void setMap(Map<String, String> map) {
        this.map = map;
    }
}

java怎么样构造函数复制一个对象

java复制对象： 一、使用clone。对象可克隆的类必须实现Cloneable接口，并且clone方法是浅克隆。 二、类实现Serializable，用ObjectOutputStream、ObjectInputStream 来复制对象。 三、可以直接new一个对象，赋值！

如何复制一个java对象

/**
 * 复制对象
 *
 * @param srcObj
 * @return
 */
public static Object depthClone(Object srcObj) {
    if (srcObj == null) {
        return null;
    }
    Object cloneObj = null;
    ByteArrayOutputStream out = null;
    ObjectOutputStream oo = null;
    ByteArrayInputStream in = null;
    ObjectInputStream oi = null;
    try {
        out = new ByteArrayOutputStream();
        oo = new ObjectOutputStream(out);
        oo.writeObject(srcObj);
        in = new ByteArrayInputStream(out.toByteArray());
        oi = new ObjectInputStream(in);
        cloneObj = oi.readObject();
    } catch (IOException e) {
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        e.printStackTrace();
    } finally {
        if (out != null) {
            try {
                out.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        if (oo != null) {
            try {
                oo.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        if (in != null) {
            try {
                in.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
        if (oi != null) {
            try {
                oi.close();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }
    return cloneObj;
}