/* * 文件名:BlobTest.java * 版权:Copyright by www.huawei.com * 描述: * 修改人:Cuigaochong * 修改时间:2015-8-25 * 跟踪单号: * 修改单号: * 修改内容: */ package com.jdbc.cgc.blob; 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.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Properties; import oracle.sql.BLOB; import org.junit.Test; /** * <一句话功能简述> <功能详细描述> * * @author 姓名 工号 * @version [版本号, 2015-8-25] * @see [相关类/方法] * @since [产品/模块版本] */ public class BlobTest { /** * <一句话功能简述>测试方法,插入一条数据,数据中有一个列是Blob <功能详细描述> * * @throws FileNotFoundException * @see [类、类#方法、类#成员] */ @Test public void test00() throws FileNotFoundException { // 注意: 对于empty_blob()应放在SQL语句中直接赋值, 使用预置语句的方式赋值无法实现. String sql = "insert into t_emp13(first_name,salary,picture) values (?,?,Empty_BLOB())"; // 查询Blob 注意进行 行锁定 后边的for update String sqlQuery = "select picture from t_emp13 where first_name = ? and salary = ? for update"; updateBlob(sql, sqlQuery, "QQA122", 1233); } /** * <一句话功能简述>更新有blob的数据库表 <功能详细描述> * * @param sqlInsert * @param sqlQuery * @param args * @see [类、类#方法、类#成员] */ public void updateBlob(String sqlInsert, String sqlQuery, Object... args) { Connection conn = null; PreparedStatement prepareStatement = null; ResultSet rs = null; OutputStream os = null; FileInputStream fis = null; try { // 现在表中插入空的Blob conn = getConn(); // 事物处理前,取消Connection的默认提交行为 conn.setAutoCommit(false); prepareStatement = conn.prepareStatement(sqlInsert); for (int i = 0; i < args.length; i++) { prepareStatement.setObject(i + 1, args[i]); } prepareStatement.executeUpdate(); BLOB blob = null; prepareStatement = conn.prepareStatement(sqlQuery); for (int i = 0; i < args.length; i++) { prepareStatement.setObject(i + 1, args[i]); } // prepareStatement.setString(1, "QQA"); rs = prepareStatement.executeQuery(); if (rs.next()) { blob = (BLOB)rs.getBlob(1); } // 得到数据库的输出流 os = blob.getBinaryOutputStream(); // 得到要插入文件的输入流 fis = new FileInputStream("Tulips.jpg"); byte[] b = new byte[1024]; int len; while (-1 != (len = fis.read(b))) { os.write(b, 0, len); } // 清空流的缓存 os.flush(); // 事物处理:如果事物处理成功则提交事物 conn.commit(); } catch (Exception e) { e.printStackTrace(); try { // 事物处理:如果出现异常 则在catch块中回滚事物 conn.rollback(); } catch (SQLException e1) { e1.printStackTrace(); } } finally { if (null != fis) { try { fis.close(); } catch (IOException e) { e.printStackTrace(); } } if (null != os) { try { os.close(); } catch (IOException e) { e.printStackTrace(); } } releaseSource(prepareStatement, conn, null); } } /** * <一句话功能简述>测试方法,查询有blob的表 <功能详细描述> * * @see [类、类#方法、类#成员] */ @Test public void test01() { String sql = "select picture from t_emp13 where first_name = ?"; queryBlob(sql, "QQA122"); } /** * <一句话功能简述>查询有Blob的表 方法 <功能详细描述> * * @param sql * @param args * @see [类、类#方法、类#成员] */ public void queryBlob(String sql, Object... args) { Connection conn = null; PreparedStatement prepareStatement = null; ResultSet rs = null; FileOutputStream fos = null; InputStream is = null; try { conn = getConn(); // 事物处理前,取消Connection的默认提交行为 conn.setAutoCommit(false); prepareStatement = conn.prepareStatement(sql); for (int i = 0; i < args.length; i++) { prepareStatement.setObject(i + 1, args[i]); } rs = prepareStatement.executeQuery(); if (rs.next()) { BLOB blob = (BLOB)rs.getBlob(1); is = blob.getBinaryStream(); fos = new FileOutputStream(new File("test.png")); byte[] b = new byte[1024]; int len; while (-1 != (len = is.read(b))) { fos.write(b, 0, len); } fos.flush(); } // 事物处理:如果事物处理成功则提交事物 conn.commit(); } catch (Exception e) { e.printStackTrace(); try { // 事物处理:如果出现异常 则在catch块中回滚事物 conn.rollback(); } catch (SQLException e1) { e1.printStackTrace(); } } finally { if (null != is) { try { is.close(); } catch (IOException e) { e.printStackTrace(); } } if (null != fos) { try { fos.close(); } catch (IOException e) { e.printStackTrace(); } } releaseSource(prepareStatement, conn, rs); } } /** * <一句话功能简述> 连接数据库 <功能详细描述> * * @return * @throws Exception * @see [类、类#方法、类#成员] */ public Connection getConn() throws Exception { String dirverName = null; String jdbcUrl = null; String user = null; String password = null; Properties propertoes = new Properties(); InputStream is = getClass().getClassLoader().getResourceAsStream("jdbc.properties"); propertoes.load(is); dirverName = propertoes.getProperty("driver"); jdbcUrl = propertoes.getProperty("jdbcURL"); user = propertoes.getProperty("user"); password = propertoes.getProperty("password"); Class.forName(dirverName); // 通过DriverManager的getConnection获取数据库连接 Connection connection = DriverManager.getConnection(jdbcUrl, user, password); return connection; } /** * <一句话功能简述>释放数据库资源 <功能详细描述> * * @param statement * @param conn * @param resultSet * @see [类、类#方法、类#成员] */ public void releaseSource(Statement statement, Connection conn, ResultSet resultSet) { if (null != resultSet) { try { resultSet.close(); } catch (SQLException e) { e.printStackTrace(); } } if (null != statement) { try { statement.close(); } catch (Exception e) { e.printStackTrace(); } } if (null != conn) { try { conn.close(); } catch (Exception e) { e.printStackTrace(); } } } }
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原文地址:http://blog.csdn.net/cuigaochong/article/details/47999469