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Oracle讀取Blob數(shù)據(jù)-通過JDBC

發(fā)布時間: 2012/8/26 16:09:48

通過JDBC讀取Blob數(shù)據(jù),演示代碼

1.
2.import java.io.File; 3.import java.io.FileOutputStream; 4.import java.io.IOException; 5.import java.io.InputStream; 6.import java.io.OutputStream; 7.import java.sql.Connection; 8.import java.sql.DriverManager; 9.import java.sql.ResultSet; 10.import java.sql.Statement; 11.
12.public class JDBC { 13.// public static void main(String[] args) throws Exception {   14.//      // 寫入BLOB數(shù)據(jù)   15.//     16.//      // 得到數(shù)據(jù)庫連接   17.//      Class.forName("Oracle.jdbc.driver.OracleDriver");   18.//   19.//      Connection con = DriverManager.getConnection(   20.//   21.//      "jdbc:Oracle:thin:@192.168.0.68:1521:myOracle", "my", "123");   22.//   23.//      // 處理事務(wù)   24.//   25.//      con.setAutoCommit(false);   26.//   27.//      Statement st = con.createStatement();   28.//   29.//      // 用for update方式鎖定數(shù)據(jù)行   30.//   31.//      ResultSet rs = st.executeQuery(   32.//   33.//      "select content from user_content where id = 2 for update");   34.//   35.//      if (rs.next()) {   36.//   37.//          // 得到j(luò)ava.sql.Blob對象，然后Cast為Oracle.sql.BLOB   38.//   39.//          Oracle.sql.BLOB blob = (oracle.sql.BLOB) rs.getBlob(1);   40.//   41.//          // 到數(shù)據(jù)庫的輸出流   42.//   43.//          OutputStream outStream = blob.getBinaryOutputStream();   44.//   45.//          // 這里用一個文件模擬輸入流   46.//   47.//          File file = new File("d:\\proxy.txt");   48.//   49.//          InputStream fin = new FileInputStream(file);   50.//   51.//          // 將輸入流寫到輸出流   52.//   53.//          byte[] b = new byte[blob.getBufferSize()];   54.//   55.//          int len = 0;   56.//   57.//          while ((len = fin.read(b)) != -1) {   58.//   59.//              outStream.write(b, 0, len);   60.//   61.//              // blob.putBytes(1,b);   62.//   63.//          }   64.//   65.//          // 依次關(guān)閉（注意順序）   66.//   67.//          fin.close();   68.//   69.//          outStream.flush();   70.//   71.//          outStream.close();   72.//   73.//          con.commit();   74.//   75.//          con.close();   76.//      }   77.// }   78.
79.    public static void main(String[] args) throws Exception { 80.        // 讀取BLOB數(shù)據(jù)   81.
82.        Class.forName("Oracle.jdbc.driver.OracleDriver"); 83.
84.        Connection con = DriverManager.getConnection(
85.
86.        "jdbc:Oracle:thin:@192.168.0.68:1521:myOracle", "my", "123"); 87.
88.        con.setAutoCommit(false); 89.
90.        Statement st = con.createStatement();
91.
92.        // 這里的SQL語句不再需要”for update”   93.
94.        ResultSet rs = st.executeQuery(
95.
96.        "select content from user_content where id = 2"); 97.
98.        if (rs.next()) { 99.
100.            java.sql.Blob blob = rs.getBlob(1); 101.
102.            InputStream ins = blob.getBinaryStream();
103.
104.            // 用文件模擬輸出流   105.
106.            File file = new File("d:\\output.txt"); 107.
108.            OutputStream fout = new FileOutputStream(file); 109.
110.            // 下面將BLOB數(shù)據(jù)寫入文件   111.
112.            byte[] b = new byte[1024]; 113.
114.            int len = 0; 115.
116.            while ((len = ins.read(b)) != -1) { 117.
118.                fout.write(b, 0, len); 119.
120.            }
121.
122.            // 依次關(guān)閉   123.
124.            fout.close();
125.
126.            ins.close();
127.
128.            con.commit();
129.
130.            con.close();
131.        }
132.    }
133.}