Silmon

package demo;import java.io.IOException;import javax.servlet.Filter;import javax.servlet.FilterChain;import javax.servlet.FilterConfig;import javax.servlet.ServletException;import javax.servle...

现在要求对一个集合里的数据进行排序，最简单的方法就是：List list = new ArrayList(); list.add(3); list.add(0); list.add(7); list.add(2); Collections.sort(list);//对指定列表按升序进行排序for(int i=0;i list = new ArrayList(); li...

Calendar c = Calendar.getInstance(); c.set(year, month-1, day); int num=c.getActualMaximum(Calendar.DAY_OF_MONTH); 

<error-page> <!-- <error-code>404</error-code> --> <exception-type>java.lang.NullPointerException</exception-type> <location>/error.html</locatio