jdbc 相关代码 存储过程
零、批处理
package cn.itcast.demo;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.junit.Test;
import cn.itcast.utils.JdbcUtils;
public class Demo3 {
/*
create table testbatch
(
id varchar(40) primary key,
name varchar(40)
);
*/
//实现批处理第一种方式
@Test
public void test1() throws SQLException{
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql1 = "insert into testbatch(id,name) values('1','aaa')";
String sql2 = "update testbatch set name='bbb' where id='1'";
st = conn.createStatement(); //list
st.addBatch(sql1);
st.addBatch(sql2);
//[3,4]
st.executeBatch();
st.clearBatch();
}finally{
JdbcUtils.release(conn, st, rs);
}
}
//实现批处理的第二种方式
@Test
public void test2() throws SQLException{
long starttime = System.currentTimeMillis();
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "insert into testbatch(id,name) values(?,?)"; //作批量插入 批量更新
st = conn.prepareStatement(sql);
for(int i=1;i<=10000006;i++){
st.setString(1, i+"");
st.setString(2, "aa" + i);
st.addBatch();
if(i%1000==0){
st.executeBatch();
st.clearBatch();
}
}
st.executeBatch();
}finally{
JdbcUtils.release(conn, st, rs);
}
long endtime = System.currentTimeMillis();
System.out.println("总花了：" + (endtime-starttime)/1000 + "秒");
}
}
一、 获取自动生成的主键 该操作仅对于insert有效
package cn.itcast.demo;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import cn.itcast.utils.JdbcUtils;
public class Demo4 {
/**
获取自动生成的主键
create table test
(
id int primary key auto_increment,
name varchar(40)
);
*/
public static void main(String[] args) throws SQLException {
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "insert into test(name) values('aaa')";
st = conn.prepareStatement(sql,Statement.RETURN_GENERATED_KEYS);
st.executeUpdate();
rs = st.getGeneratedKeys();
if(rs.next()){
System.out.println(rs.getInt(1));
}
}finally{
JdbcUtils.release(conn, st, rs);
}
}
}
package cn.itcast.demo;
import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Types;
import cn.itcast.utils.JdbcUtils;
public class Demo5 {
/**
调用存储过程
* @throws SQLException
*/
public static void main(String[] args) throws SQLException {
Connection conn = null;
CallableStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
st = conn.prepareCall("{call demoSp(?,?)}");
st.setString(1, "aaaaa");
st.registerOutParameter(2, Types.VARCHAR); //这个地方是设置数据库的编码类型
st.execute();
System.out.println(st.getString(2));
}finally{
JdbcUtils.release(conn, st, rs);
}
}
}
三、读文件
package cn.itcast.demo;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Reader;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.junit.Test;
import cn.itcast.utils.JdbcUtils;
public class Demo1 {
/**读写大文本
create table testclob
(
id varchar(40) primary key,
resume text
);
*/
@Test
public void insert() throws SQLException, FileNotFoundException{
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "insert into testclob(id,resume) values(?,?)";
st = conn.prepareStatement(sql);
st.setString(1, "1");
File file = new File("src/1.txt");
FileReader reader = new FileReader(file);
st.setCharacterStream(2, reader, (int) file.length());
int num = st.executeUpdate();
if(num>0){
System.out.println("插入成功！！");
}
}finally{
JdbcUtils.release(conn, st, rs);
}
}
@Test
public void read() throws SQLException, IOException{
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "select id,resume from testclob where id='1'";
st = conn.prepareStatement(sql);
rs = st.executeQuery();
if(rs.next()){
//String resume = rs.getString("resume");
Reader reader = rs.getCharacterStream("resume");
FileWriter writer = new FileWriter("c:\\1.txt");
try {
int len = 0;
char buffer[] = new char[1024];
while ((len = reader.read(buffer)) > 0) {
writer.write(buffer, 0, len);
}
} finally {
if (reader != null) {
reader.close();
}
writer.close();
}
}
}finally{
JdbcUtils.release(conn, st, rs);
}
}
}
package cn.itcast.demo;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import org.junit.Test;
import cn.itcast.utils.JdbcUtils;
public class Demo2 {
/*
create table testblob
(
id varchar(40) primary key,
image blob
);
*/
@Test
public void insert() throws SQLException, FileNotFoundException{
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "insert into testblob(id,image) values(?,?)";
st = conn.prepareStatement(sql);
st.setString(1, "1");
File file = new File("src/1.jpg");
FileInputStream in = new FileInputStream(file);
st.setBinaryStream(2, in, (int) file.length());
st.executeUpdate();
}finally{
JdbcUtils.release(conn, st, rs);
}
}
@Test
public void read() throws SQLException, IOException{
Connection conn = null;
PreparedStatement st = null;
ResultSet rs = null;
try{
conn = JdbcUtils.getConnection();
String sql = "select id,image from testblob where id='1'";
rs = conn.prepareStatement(sql).executeQuery();
if(rs.next()){
InputStream in = rs.getBinaryStream("image");
OutputStream out = new FileOutputStream("c:\\1.jpg");;
try {
int len = 0;
byte buffer[] = new byte[1024];
while ((len = in.read(buffer)) > 0) {
out.write(buffer, 0, len);
}
} finally {
if (in != null)
in.close();
if (out != null)
out.close();
}
}
}finally{
JdbcUtils.release(conn, st, rs);
}
}
}