/*
實現(xiàn)的功能：
 用數(shù)據(jù)庫存儲文本數(shù)據(jù)，并且讀取出來放在當(dāng)前項目里
分析：
 難度不是很大，關(guān)鍵是掌握文件流，數(shù)據(jù)庫的操作不是很多，但是文件流的讀寫比較多
日期：20131003
作者：煙大陽仔
*/
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.建立連接
   conn=JdbcUtils.getConnection();
   //單例設(shè)計模式
   conn=JdbcUtilsSingle.getInstance().getConnection();
   //3.創(chuàng)建語句
   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.執(zhí)行語句
   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.建立連接
   conn=JdbcUtils.getConnection();
   //單例設(shè)計模式
   conn=JdbcUtilsSingle.getInstance().getConnection();
   //3.創(chuàng)建語句
   st=conn.createStatement();
   //4.執(zhí)行語句
   resultset=st.executeQuery("select text from ckb_test");
   //5.處理結(jié)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);
  }
 }
}
/*
實現(xiàn)的功能：
 用數(shù)據(jù)庫存儲圖片數(shù)據(jù)，并且讀取出來放在當(dāng)前項目里
分析：
 難度不是很大，關(guān)鍵是掌握字節(jié)流，數(shù)據(jù)庫的操作不是很多，但是文件流的讀寫比較多，注意更改圖片的目錄
日期：20131003
作者：煙大陽仔
*/
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.建立連接
   conn=JdbcUtils.getConnection();
   //單例設(shè)計模式
   conn=JdbcUtilsSingle.getInstance().getConnection();
   //3.創(chuàng)建語句
   String sql="insert into blob_test(big_bit) values(?)";
   prest=conn.prepareStatement(sql);
   File file=new File("C:\\Documents and Settings\\Administrator\\My Documents\\My Pictures\\cxg.jpg");
   InputStream in=new BufferedInputStream(new FileInputStream(file));
   prest.setBinaryStream(1, in, (int)file.length());
   //4.執(zhí)行語句
   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.建立連接
   conn=JdbcUtils.getConnection();
   //單例設(shè)計模式
   conn=JdbcUtilsSingle.getInstance().getConnection();
   //3.創(chuàng)建語句
   st=conn.createStatement();
   //4.執(zhí)行語句
   resultset=st.executeQuery("select big_bit from blob_test");
   //5.處理結(jié)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);
  }
 }
}