烦人的tomcat

final ：一个在运行时被初始化的值，而你不希望他被改变。


tomcat出现了各种问题；端口，127.0.0.1不能被连接......


tomcat7.0.82端口82


Several ports (8005, 8080, 8009) required by Tomcat v5.5 Server at localhost are already in use. The server may already be running in another process, or a system process may be using the port. To start this server you will need to stop the other process or change the port number(s).




原因：端口8005, 8080, 8009被占用了。可能是在打开Tomcat的情况下关闭了Eclipse，或是Eclipse非正常关闭，导致先前的Tomcat没有被关闭，端口占用。或是其他软件占用了tomcat的端口号。


Connection to 127.0.0.1:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.


public:
    template
    static List asList(T a);
共出现了三个T，第一个是用来声明类型参数的，后面的两个才是泛型的实现


在用Tomcat与jetty测试JFinal的时候都出现了这种情况。
Connection to 127.0.0.1:5432 refused.Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.


Jetty的HelloWorld虽然出现错误，  但是在http：//localhost/hello上仍能显示结果。


Tomcat的是在https://git.oschina.net/dongcb678/JfinalUIB导入的blog。还没弄懂，正在看代码。