JAVA处理XML

<xml>

 <ToUserName><![CDATA[toUser]]></ToUserName>

 <FromUserName><![CDATA[fromUser]]></FromUserName> 

 <CreateTime>1348831860</CreateTime>

 <MsgType><![CDATA[text]]></MsgType>

 <Content><![CDATA[this is a test]]></Content>

 <MsgId>1234567890123456</MsgId>

</xml>

请问JAVA怎么读取和构建这类XML代码？