java 深度复制

    最近的系统改造，遇到了前人写的PropertyUtilsBean.( dest, orig)
方法来复制对象，想到自己对Java API了解到太少，以后可以多多学习。

    由于改造后的系统运用JPA技术，将以前的JOPO转换成了实体Bean，并且实体Bean间建立起了表之间的关联关系（一对多、多对一、多对多之乎者也的），调试程序时发现copyProperties方法失效了，不解之下，找到了JavaSE的API一窥究竟，原来该方法不支持续对象的嵌套复制，API中如是说：

Note that this method is intended to perform a "shallow copy" of the properties and so complex properties (for example, nested ones) will not be copied.

Note, that this method will not copy a List to a List, or an Object[] to an Object[]. It's specifically for copying JavaBean properties.

    于是在网上借鉴了用输入输出流进行深度复制的方法，问题终于解决了，在此感谢豁然开朗的代码：

private static Object depthClone(Object srcObj){
74. Object cloneObj = null;
75. try {
76. ByteArrayOutputStream out = new ByteArrayOutputStream();
77. ObjectOutputStream oo = new ObjectOutputStream(out);
78. oo.writeObject(srcObj);
79.
80. ByteArrayInputStream in = new ByteArrayInputStream(out.toByteArray());
81. ObjectInputStream oi = new ObjectInputStream(in);
82. cloneObj = oi.readObject();
83. } catch (IOException e) {
84. e.printStackTrace();
85. } catch (ClassNotFoundException e) {
86. e.printStackTrace();
87. }
88. return cloneObj;
89. }