JdbcUtil JDBC工具类

import java.sql.*;
/**
* @JDBC工具类
* 功能：
* 1 获得Connection
* 2 String转Integer
* 3 select table
* 4 读取任意结果集
* 5 关连接
*/
public class JdbcUtil {
/**
*
* @加载类
*/
static {
try {
String driverClassName = "oracle.jdbc.driver.OracleDriver";
Class.forName(driverClassName);
}catch(Exception e) {
e.printStackTrace();
}
}
/**
* @获得Connection
*/
public static Connection getConnection() {
Connection con = null;
try {
String url = "jdbc:oracle:thin:@192.168.0.20:1521:tarena";
// 协议＋主机地址＋资源名称
String userName = "openlab";
String pwd = "open123";
con = DriverManager.getConnection(url, userName, pwd);
} catch (Exception e) {
e.printStackTrace();
}
return con;
}
/**
* @String转Integer
*/
public static Integer toInt(String num) {
Integer i = null;
try {
i = Integer.parseInt(num);
} catch (Exception e) {
System.out.println(e.getMessage());
}
return i;
}
/**
* @select table
*/
public static void selectTable(String tableName){
Connection con = null;
PreparedStatement ps = null;
ResultSet rs = null;
try{
con = JdbcUtil.getConnection();
String sql = "select * from "+tableName;
ps = con.prepareStatement(sql);
rs = ps.executeQuery();

ResultSetMetaData meta = rs.getMetaData();
int cols = meta.getColumnCount();
StringBuffer sb = new StringBuffer();
while(rs.next()){
for (int i = 1; i <= cols; i++) {
sb.append(meta.getColumnName(i)+" = ");
sb.append(rs.getString(i)+" ");
}
sb.append("\n");
}
System.out.println(sb.toString());
}catch(Exception e){
System.out.println(e.getMessage());
}finally{
JdbcUtil.close(rs, ps, con);
}

}
/**
* 读取任意结果集
* @param rs
*/
public static void printRs(ResultSet rs) {
try{
ResultSetMetaData meta = rs.getMetaData();
int cols = meta.getColumnCount();
StringBuffer sb = new StringBuffer();
int n = 0;
while(rs.next()){
for (int i = 1; i <= cols; i++) {
sb.append(meta.getColumnName(i)+" = ");
sb.append(rs.getString(i)+" ");
}
sb.append("\n");
n++;
}
System.out.println(sb.toString());
System.out.println("找到-"+n+"条记录");
}catch(Exception e){
System.out.println(e.getMessage());
}
}
/**
* @关连接
*/
public static void close(ResultSet rs, Statement stmt, Connection con) {
/**
* 要按照顺序关 rs-->stmt-->con
*/
try {
if (rs != null)
rs.close();
} catch (Exception e) {
e.printStackTrace();
}
try {
if (stmt != null)
stmt.close();// 对象还在，不过不能用了,对象是垃圾回收器去回收的！
} catch (Exception e) {
e.printStackTrace();
}
try {
if (con != null)
con.close();
} catch (Exception e) {
e.printStackTrace();
}
}

}

自己写的JDBC工具类 望高手改进
并且说一下，本人新手！各位高手看看还有什么功能应该实现的，说说。



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