JDBC事務、批處理、大物件的基本使用
阿新 • • 發佈：2018-11-21
一、測試事務的概念和用法
package com.chenfu.test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; /** * 測試事務的概念和用法 * @author Administrator * */ public class Demo06 { public static void main(String[] args) { Connection conn = null; PreparedStatement ps1 = null; PreparedStatement ps2 = null; try { //載入驅動類 Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testjdbc","root","123456"); conn.setAutoCommit(false);//JDBC預設自動提交 ps1 = conn.prepareStatement("insert into t_use (username,pwd) values(?,?)"); ps1.setObject(1, "chenfu"); ps1.setObject(2, "123456"); ps1.execute(); System.out.println("插入一個使用者，chenfu"); try { Thread.sleep(6000); } catch (InterruptedException e) { e.printStackTrace(); } ps2 = conn.prepareStatement("insert into t_user (username,pwd) values(?,?)"); ps2.setObject(1, "xvbolai"); ps2.setObject(2, "123456"); ps2.execute(); System.out.println("第二個使用者，徐伯萊"); conn.commit(); } catch (ClassNotFoundException e) { e.printStackTrace(); try { conn.rollback();//回滾 } catch (SQLException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } } catch (SQLException e) { e.printStackTrace(); }finally{//resultSet-->statment-->connection這樣的順序 try { if(ps1!=null){ ps1.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { if(conn!=null){ conn.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
二、測試批量處理的基本用法
package com.chenfu.test; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; /** * 測試批量處理的基本用法 * @author Administrator * */ public class Demo05 { public static void main(String[] args) { Connection conn = null; Statement stmt = null; ResultSet rs = null; try { //載入驅動類 Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testjdbc","root","123456"); conn.setAutoCommit(false);//設為手動提交！ long start = System.currentTimeMillis(); stmt = conn.createStatement(); for(int i = 0; i < 2900; i ++){ stmt.addBatch("insert into t_user (username,psw,regtime) values('gao"+i+"','666666',now())"); } stmt.executeBatch(); conn.commit(); long end = System.currentTimeMillis(); System.out.println("插入29000資料耗時"+(end-start)); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); }finally{//resultSet-->statment-->connection這樣的順序 try { try { if(rs!=null){ rs.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } if(stmt!=null){ stmt.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { if(conn!=null){ conn.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
三、大物件的使用
package com.chenfu.test; import java.io.IOException; import java.io.Reader; import java.sql.Clob; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.text.DateFormat; import java.text.ParseException; import java.text.SimpleDateFormat; /** * 測試CLOB 文字大物件的使用 * 包含：將字串、檔案內容插入資料庫中CLOB欄位、將CLOB欄位取出來 * @author Administrator * */ public class Demo09 { public static void main(String[] args) { Connection conn = null; PreparedStatement ps = null; ResultSet rs = null; Reader r =null; try { //載入驅動類 Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testjdbc","root","123456"); ps = conn.prepareStatement("insert into t_user (username,myInfo) values (?,?)"); ps.setString(1, "高旗"); // ps.setClob(2, new FileReader(new File("d:/a.txt")));//將文字檔案內容直接輸入到資料庫中 //將程式中的字串輸入到資料庫CLOB的欄位中 // ps.setClob(2, new BufferedReader(new InputStreamReader(new ByteArrayInputStream("aaaaa".getBytes())))); ps = conn.prepareStatement("select * from t_user where id=?"); ps.setObject(1, 4); rs = ps.executeQuery(); while(rs.next()){ Clob c = rs.getClob("myInfo"); r = c.getCharacterStream(); int temp = 0 ; while((temp=r.read())!=-1){ System.out.println((char)temp); } } } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); }finally{//resultSet-->statment-->connection這樣的順序 try { if(r!=null){ r.close(); } } catch (IOException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } try { if(ps!=null){ ps.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { if(conn!=null){ conn.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } } }
package com.chenfu.test;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Reader;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
/**
* 測試BLOB 二進位制大物件的使用
* @author Administrator
*
*/
public class Demo10 {
public static void main(String[] args) {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
InputStream is =null;
OutputStream os = null;
try {
//載入驅動類
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/testjdbc","root","123456");
// ps = conn.prepareStatement("insert into t_user (username,headImg) values (?,?)");
// ps.setString(1, "高旗");
// ps.setBlob(2, new FileInputStream("d:/icon.jpg"));
// ps.execute();
ps = conn.prepareStatement("select * from t_user where id=?");
ps.setObject(1, 8);
rs = ps.executeQuery();
while(rs.next()){
Blob b = rs.getBlob("headImg");
is = b.getBinaryStream();
os = new FileOutputStream("d:/a.jpg");
int temp = 0 ;
while((temp=is.read())!=-1){
os.write(temp);
}
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{//resultSet-->statment-->connection這樣的順序
try {
if(is!=null){
is.close();
}
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
if(os!=null){
os.close();
}
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
try {
if(ps!=null){
ps.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}