java的help文档，中文版，查询方便-java' s help documents, the Chinese version to facilitate query

这个是关于Java类库的介绍文档，可以方便Java开发人员查询相关的资料，方便、合适，不容错过啊！-This is a document about the introduction of Java class libraries, Java developers can easily query the information relevant, convenient, appropriate, ah not to be missed!