Question

为什么这个小程序在applet查看器中没有显示在JSP中？

我想在我的jsp代码中添加一个applet。请帮我做同样的事。我想在我的应用程序中嵌入一个计算器applet应用程序。我添加了java类文件，jsp文件和项目目录结构。

DateTime.jsp

    <%@page import="java.text.DateFormat"%>
    <%@page contentType="text/html" pageEncoding="UTF-8"%>
    <%@page import="java.util.*" %>
    <!DOCTYPE html>
    <html>
        <head>
            <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
            <title>Date Time Page</title>
        </head>
        <body>
            <h1>Hello World!</h1>
            <p>Today is - </p>
            <% DateFormat df = DateFormat.getDateInstance(DateFormat.FULL);
                Date Today = new Date();
                String msg = df.format(Today);
                out.println(msg);
            %>
            <h1> JSP Plugin Example </h1>

            <jsp:plugin align="middle" type="applet" code="calculator.class" >
                <jsp:fallback> <p>Unable to load applet</p>
                </jsp:fallback>
            </jsp:plugin>
        </body>
    </html>

calculator.java

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author Sampad
 */
import java.applet.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.TextEvent;
import java.awt.event.TextListener;
public class calculator extends Applet implements ActionListener, TextListener

{
 String s,s1,s2,s3,s4;
 Button b1,b2,b3,b4,b5,b6,b7,b8,b9,b0;
 Button add,sub,eq,cl,mul,div;
 TextField t1;
 int a,b,c;

 public void init()
 {
  t1=new TextField(10);
  b1=new Button("1");
  b2=new Button("2");
  b3=new Button("3");
  b4=new Button("4");
  b5=new Button("5");
  b6=new Button("6");
  b7=new Button("7");
  b8=new Button("8");
  b9=new Button("9");
  b0=new Button("0");
  add=new Button("+");
  sub=new Button("-");
  mul=new Button("*");
  div=new Button("/");
  eq=new Button("=");
  cl=new Button("Clear");



  GridLayout gb=new GridLayout(4,5);
  setLayout(gb);


  add(t1);
  add(b1);
  add(b2);
  add(b3);
  add(b4);
  add(b5);
  add(b6);
  add(b7);
  add(b8);
  add(b9);
  add(b0);
  add(add);
  add(sub);
  add(mul);
  add(div);
  add(eq);
  add(cl);

  b1.addActionListener(this);
  b2.addActionListener(this);
  b3.addActionListener(this);
  b4.addActionListener(this);
  b5.addActionListener(this);
  b6.addActionListener(this);
  b7.addActionListener(this);
  b8.addActionListener(this);
  b9.addActionListener(this);
  b0.addActionListener(this);
  add.addActionListener(this);
  sub.addActionListener(this);
  mul.addActionListener(this);
  div.addActionListener(this);
  eq.addActionListener(this);
  cl.addActionListener(this);
  paint();
  //t1.addTextListener(this);
 }
 public void paint()
 {
  setBackground(Color.green);
 }

 public void actionPerformed(ActionEvent e)
 {
  s=e.getActionCommand();
  if(s.equals("0")||s.equals("1")||s.equals("2")||
s.equals("3")||s.equals("4")||s.equals("5")||s.equals("6")||s.equals("7")||s.equals("8")||
s.equals("9")||s.equals("0"))
  {
   s1=t1.getText()+s;
   t1.setText(s1);
  }
  if(s.equals("+"))
  {
     s2=t1.getText();
     t1.setText("");
     s3="+";
  }
  if(s.equals("-"))
  {
     s2=t1.getText();
     t1.setText("");
     s3="-";
  }
  if(s.equals("*"))
  {
     s2=t1.getText();
     t1.setText("");
     s3="*";
  }
  if(s.equals("*"))
  {
     s2=t1.getText();
     t1.setText("");
     s3="*";
  }
  if(s.equals("="))
  {
   s4=t1.getText();
   a=Integer.parseInt(s2);
   b=Integer.parseInt(s4);
   if(s3.equals("+"))
    c=a+b;
   if(s3.equals("-"))
    c=a-b;

   t1.setText(String.valueOf(c));
  }
  if(s.equals("Clear"))
  {
   t1.setText("");
  }
 }
 public void textValueChanged(TextEvent e)
 {

 }

}

在JSP页面中使用applet

为什么这个小程序在applet查看器中没有显示在JSP中？

0 个答案: