Java Workshop--(3) JSP

上一期PreparedStatement的答案如下

import java.sql.*;
class JPC_JDBCSample2 {
public static void main(String args[]) {
Connection con = null;
PreparedStatement pstmt = null;
String sql = null;
ResultSet rs = null;
String div = null; // Division
short total= 0; // Total amount of managers
// Set a String input in command line as in the division variable
if(args.length >0){
div = args[0];
}else{
System.out.println("Please input a division");
return;
}
try {
// Load the driver
Class.forName("COM.ibm.db2.jdbc.app.DB2Driver");
// Set JDBC URL in a variable
// The URL is jdbc:db2:dbname
String url = "jdbc:db2:sample";
// Connect to the DB specified by the JDBC URL
// with the user ID (db2admin) and the password (password)
con = DriverManager.getConnection(url,"db2admin","password");
// +++(1) Specify a SQL statement
sql = "SELECT DEPTNAME,MANAGER FROM org WHERE DIVISION =?";
// +++(2) Create a PreparedStatement object
pstmt = con.prepareStatement(sql);
// +++(3) Set a parameter in the PreparedStatement object
pstmt.setString(1, div);
// +++(4) Execute a query
rs = pstmt.executeQuery();
// +++(5)(6)Retrieve the result from the ResultSet
// +++ object and display it
System.out.println("***** " + div + " *****");
while (rs.next()) {
String dname = rs.getString(1);
short manager = rs.getShort(2);
System.out.print( dname+": ");
System.out.println( manager);
total += manager;
}
System.out.println("Total: "+total);
} catch (ClassNotFoundException e){
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}finally{
try{
// Release resources
rs.close();
pstmt.close();
con.close();
}catch(SQLException e){
e.printStackTrace();
}
}
}
}

这里给出了一个javabean的代码，然后请试着给出jsp和javabean交互的代码

package jpc;
/*
* AddBean.java
*
*/
public class AddBean {
private int data1;
private int data2;
/**
*
* Constructor
*/
public AddBean () {
}
/**
* Return the value of the Data1 as a String.
*/
public String getData1() {
return String.valueOf(data1);
}
/**
* Set Data1
*/
public void setData1(String str) {
try {
this.data1 = Integer.parseInt(str);
}
catch (NumberFormatException e) {
this.data1 = 0;
}
}
/**
* Return the value of the Data2 as a String.
*/
public String getData2() {
return String.valueOf(data2);
}
/**
* Set Data2
*/
public void setData2(String str) {
try {
this.data2 = Integer.parseInt(str);
}
catch (NumberFormatException e) {
this.data2 = 0;
}
}
/**
* Return the result of the addition as a String.
*/
public String getResult() {
return String.valueOf(data1 + data2);
}
}

以下是调用javabean的jsp代码框架。

<html>
<head>
<title> Exercise JSP </title>
</head>
<body>
<h1> Exercise JSP </h1>
<hr>
[ 1 ]
<form action="/JPC/jsp/Add.jsp" method=POST>
DATA1 <input type=text name=param1 ><br>
DATA2 <input type=text name=param2 ><br>
<input type=submit value="Submit">
</form>
[ 2 ]
[ 3 ]
<h2>
[ 4 ]
[ 5 ]
</h2>
</body>
</html>

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