本文实例讲述了JDBC编程实现文件、图片的存储方法。分享给大家供大家参考,具体如下:
/* 实现的功能: 用数据库存储文本数据,并且读取出来放在当前项目里 分析: 难度不是很大,关键是掌握文件流,数据库的操作不是很多,但是文件流的读写比较多 日期:20131003 作者:烟大阳仔 */ public class Ckb_test { public static void main(String[] args) throws SQLException, IOException { // TODO Auto-generated method stub read(); } static void create() throws SQLException, IOException { Connection conn=null; PreparedStatement prest=null; ResultSet resultset=null; try { //2.建立连接 conn=JdbcUtils.getConnection(); //单例设计模式 conn=JdbcUtilsSingle.getInstance().getConnection(); //3.创建语句 String sql="insert into ckb_test(text) values("; prest=conn.prepareStatement(sql); File file=new File("src/cn/com/JDBC/JdbcUtils.java"); Reader reader=new BufferedReader(new FileReader(file)); prest.setCharacterStream(1, reader, (int)file.length()); //4.执行语句 int i=prest.executeUpdate(); reader.close(); System.out.println("i="+i); } finally { JdbcUtils.free(resultset, prest, conn); } } static void read() throws SQLException, IOException { Connection conn=null; Statement st=null; ResultSet resultset=null; try { //2.建立连接 conn=JdbcUtils.getConnection(); //单例设计模式 conn=JdbcUtilsSingle.getInstance().getConnection(); //3.创建语句 st=conn.createStatement(); //4.执行语句 resultset=st.executeQuery("select text from ckb_test"); //5.处理结果 while(resultset.next()) { Clob clob=resultset.getClob(1); Reader reader=clob.getCharacterStream(); //reader=resultset.getCharacterStream(1); File file=new File("JdbcUtils.java"); Writer writer=new BufferedWriter(new FileWriter(file)); char[] buff=new char[1024]; for(int i=0;(i=reader.read(buff))>0;) { writer.write(buff,0,i); } writer.close(); reader.close(); } } finally { JdbcUtils.free(resultset, st, conn); } } } /* 实现的功能: 用数据库存储图片数据,并且读取出来放在当前项目里 分析: 难度不是很大,关键是掌握字节流,数据库的操作不是很多,但是文件流的读写比较多,注意更改图片的目录 日期:20131003 作者:烟大阳仔 */ public class PictureBlob { public static void main(String[] args) throws SQLException, IOException { read(); } static void create() throws SQLException, IOException { Connection conn=null; PreparedStatement prest=null; ResultSet resultset=null; try { //2.建立连接 conn=JdbcUtils.getConnection(); //单例设计模式 conn=JdbcUtilsSingle.getInstance().getConnection(); //3.创建语句 String sql="insert into blob_test(big_bit) values("; prest=conn.prepareStatement(sql); File file=new File("C:Documents and SettingsAdministratorMy DocumentsMy Picturescxg.jpg"); InputStream in=new BufferedInputStream(new FileInputStream(file)); prest.setBinaryStream(1, in, (int)file.length()); //4.执行语句 int i=prest.executeUpdate(); in.close(); System.out.println("i="+i); } finally { JdbcUtils.free(resultset, prest, conn); } } static void read() throws SQLException, IOException { Connection conn=null; Statement st=null; ResultSet resultset=null; try { //2.建立连接 conn=JdbcUtils.getConnection(); //单例设计模式 conn=JdbcUtilsSingle.getInstance().getConnection(); //3.创建语句 st=conn.createStatement(); //4.执行语句 resultset=st.executeQuery("select big_bit from blob_test"); //5.处理结果 while(resultset.next()) { Blob blob=resultset.getBlob(1); InputStream in=blob.getBinaryStream(); //reader=resultset.getCharacterStream(1); File file=new File("1.jpeg"); OutputStream out=new BufferedOutputStream(new FileOutputStream(file)); byte[] buff=new byte[1024]; for(int i=0;(i=in.read(buff))>0;) { out.write(buff,0,i); } out.close(); in.close(); } } finally { JdbcUtils.free(resultset, st, conn); } } }
希望本文所述对大家Java程序设计有所帮助。