java操作oracle数据库中的blob字段

oracle中的BLOB字段是存储2进制的文件，比如文件，图片等。
1、把本地文件写入数据库
package com.data;
import java.io.File;
import java.io.FileInputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement;
public class WriteBlob {
/**
* beckham 2009-12-7 下午09:47:36
*/
public static void main(String[] args) throws Exception {
Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();
String url = "jdbc:oracle:thin:@localhost:1521:menhu";
String user = "zm";
String password = "zm";
Connection conn = DriverManager.getConnection(url, user, password);
// 设置手动提交
conn.setAutoCommit(false);
Statement sta = null;
ResultSet rs = null;
PreparedStatement ps = null;
// 插入空值
String sql = "insert into mytest values(3,empty_blob()) ";
sta = conn.createStatement();
sta.executeUpdate(sql);
conn.commit();
// 锁定并编辑当前数据
sql = "select images from mytest where id=3 for update";
rs = sta.executeQuery(sql);
if (rs.next()) {
oracle.sql.BLOB b = (oracle.sql.BLOB) rs.getBlob("images");
// 输入流
OutputStream os = b.getBinaryOutputStream();
// 输出流
FileInputStream fiis = new FileInputStream(new File("1.doc"));
// 入库
byte[] tmp = new byte[1024];
int a = 0;
while ((a = fiis.read(tmp)) != -1) {
os.write(tmp, 0, a);
os.flush();
}
os.close();
fiis.close();
}
conn.commit();
rs.close();
sta.close();
conn.close();
}
}
 
2、从数据库中读取Blob字段数据
package com.data;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
public class ReadBlob {
/**
* beckham 2009-12-8 下午03:49:30
*/
public static void main(String[] args) throws Exception