网络及数据库编程设计

JAVA程序设计实验报告

四．实验结果分析（含执行结果验证、输出显示信息、图形、调试过程中所遇的问题及处理方法等）// CreateTable.java

// InsertTable.java

// UpdateTable.java

问题：此次实验是Java连接MySQL，自己之前对MySQL基本语句有过熟悉和了解，MySQL 语句方面倒是没什么问题，但是使用Java操作起来还是比较生疏，需要参考老师的代码，以后要多加练习。

（注意：内容写不下时可另附页。）

附：

// DBconfig.java（续）

/**

* 建立连接

* @return conn

*/

public static Connection getConnection() {

try {

try {

// 加载驱动程序

Class.forName(JDBC_DRIVER);

System.out.println("加载成功");

} catch (https://www.360docs.net/doc/5814985160.html,ng.ClassNotFoundException e) {

System.out.println("ForName: " + e.getMessage());

}

conn = DriverManager.getConnection(JDBC_URL, JDBC_USERNAME, JDBC_PASSWORD);

} catch (Exception e) {

e.printStackTrace();

}

return conn;

}

/**

* 关闭连接

* @param rs

* @param st

* @param ps

* @param conn

*/

public static void closeConnection(ResultSet rs, Statement st, PreparedStatement ps, Connection conn) {

try {

if (null != rs) {

rs.close();

}

if (null != st) {

st.close();

}

if (null != ps) {

ps.close();

}

if (null != conn) {

conn.close();

}

} catch (Exception e) {

System.out.println("Close connection error");

e.printStackTrace();

}

}

}

// CreateTable.java

/*

* 若尘

*/

package five;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.Statement;

/**

* 创建职工表

* @author ruochen

* @version 1.0

*/

public class CreateTable {

public static void main(String[] args) {

Connection conn = DBConfig.getConnection();

try {

Statement st = conn.createStatement();

ResultSet rs = conn.getMetaData().getTables(null, null, "workers", null);

if (rs.next()) {

System.out.println("表已经存在");

} else {

String sql = "create table workers ( "

+ "id varchar(10),"

+ "name varchar(20),"

+ "sex varchar(5),"

+ "salary int,"

+ "title varchar(10)" + ")";

st.executeUpdate(sql);

System.out.println("创建成功");

}

DBConfig.closeConnection(rs, st, null, conn);

} catch (Exception e) {

System.out.println("SQLException: " + e.getMessage());

}

}

}

// InsertTable.java

/*

* 若尘

*/

package five;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

/**

* 向表中插入信息

* @author ruochen

* @version 1.0

*/

public class InsertTable {

public static void main(String[] args) {

Connection conn = DBConfig.getConnection();

String sql1 = "insert into workers values ('1001', '丁卫国', '男', 650, '助工')";

String sql2 = "insert into workers values ('1002', '张小华', '女', 1000, '工程师')";

String sql3 = "insert into workers values ('1003', '丁涛', '男', 2500, '高工')";

String sql = " select * from workers";

try {

Statement st = conn.createStatement();

st.executeUpdate(sql1);

st.executeUpdate(sql2);

st.executeUpdate(sql3);

System.out.println("insert success");

ResultSet rs = st.executeQuery(sql);

while (rs.next()) {

System.out.println(rs.getString("id") + "\t" + rs.getString("name") + "\t"

+ rs.getString("sex") + "\t" + rs.getInt("salary") + "\t" + rs.getString("title"));

}

DBConfig.closeConnection(rs, st, null, conn);

} catch (SQLException e) {

e.printStackTrace();

}

}

}

// UpdateTable.java

/*

* 若尘

*/

package five;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.Statement;

/**

* 更新表

* @author ruochen

* @version 1.0

*/

public class UpdateTable {

public static void main(String[] args) {

Connection conn = DBConfig.getConnection();

try {

Statement st = conn.createStatement();

String sql1 = "update workers set salary = salary + 50";

String sql2 = "select * from workers";

st.executeUpdate(sql1);

System.out.println("Update success");

ResultSet rs = st.executeQuery(sql2);

while (rs.next()) {

System.out.println(rs.getString("id") + "\t" + rs.getString("name") + "\t"

+ rs.getString("sex") + "\t" + rs.getInt("salary") + "\t" + rs.getString("title"));

}

DBConfig.closeConnection(rs, st, null, conn);

} catch (Exception e) {

e.printStackTrace();

}

}

}