Oracle blob 的整理

Oracle 数据库 xt_inform （title ，text，……）title 主键 varchar ， text blob
添加数据：（insert into）
public boolean addTongGao(TongGao tg) {
  boolean addflag = false;
  
  String strFilelinks = this.getStrFilelinks(tg);
  java.sql.Date issuedate = this.getSQLDate(tg.getIssuedate());
  java.sql.Date enddate = this.getSQLDate(tg.getEnddate());
  String sql = "";
  
  Connection conn = db.getConn();
  try {
   conn.setAutoCommit(false);
   sql = "Insert Into xt_inform(title, text, issuedate, enddate, category, department, publisher, top, filelinks) Values(?,empty_blob(),?,?,?,?,?,?,?)";
   Object[] params = {tg.getTitle(),
     issuedate,
     enddate,
     tg.getCategory(),
     tg.getDepartment(),
     tg.getPublisher(),
     tg.getTop(),
     strFilelinks};
   PreparedStatement pstmt = db.getPstmt(conn, sql, params);
   int count = db.getCount(pstmt);
   pstmt.close();
   
   sql = "select text from xt_inform where title = ? for update";
   Object[] params1 = {tg.getTitle()};
   pstmt = db.getPstmt(conn, sql, params1);
   ResultSet rs = db.getResultSet(pstmt);
   if(rs != null) {
    rs.next();
    oracle.sql.BLOB blob = (BLOB) rs.getBlob("text");
    OutputStream out = blob.getBinaryOutputStream();
    out.write(tg.getText().getBytes(), 0, tg.getText().length());
    out.flush();
    out.close();
   }
   conn.commit();
   conn.setAutoCommit(true);
   rs.close();
   pstmt.close();
   addflag = true;
  } catch (SQLException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } catch (IOException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } finally {
   db.close(conn);
  }
  return addflag;
 }
更新（update set）
 public boolean updateTongGao(TongGao tg) {
  boolean updateflag = false;
  
  String strFilelinks = this.getStrFilelinks(tg);
  java.sql.Date issuedate = this.getSQLDate(tg.getIssuedate());
  java.sql.Date enddate = this.getSQLDate(tg.getEnddate());
  
  Connection conn = db.getConn();
  try {
   conn.setAutoCommit(false);
   
   String sql = "Update xt_inform Set title = ?, text = empty_blob(), issuedate = ?, enddate = ?, category = ?, department = ?, publisher = ?, top = ?, filelinks = ? Where title = ?";
   Object[] params = {tg.getTitle(),
     issuedate,
     enddate,
     tg.getCategory(),
     tg.getDepartment(),
     tg.getPublisher(),
     tg.getTop(),
     strFilelinks,
     tg.getTitle()};
   PreparedStatement pstmt = db.getPstmt(conn, sql, params);
   int count = db.getCount(pstmt);
   pstmt.close();
   
   sql = "select text from xt_inform where title = ? for update";
   Object[] params1 = {tg.getTitle()};
   pstmt = db.getPstmt(conn, sql, params1);
   ResultSet rs = db.getResultSet(pstmt);
   if(rs != null) {
    rs.next();
    oracle.sql.BLOB blob = (BLOB) rs.getBlob("text");
    OutputStream out = blob.getBinaryOutputStream();
    out.write(tg.getText().getBytes(), 0, tg.getText().length());
    out.flush();
    out.close();
   }
   conn.commit();
   conn.setAutoCommit(true);
   rs.close();
   pstmt.close();
   updateflag = true;
  } catch (SQLException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } catch (IOException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } finally {
   db.close(conn);
  }
  return updateflag;
 }
读取（select from）
 public TongGao getTongGaoByTitle(String title) {
  TongGao tg = null;
  
  Connection conn = db.getConn();
  try {
   conn.setAutoCommit(false);
   String sql = "Select * From xt_inform Where title = ? ";
   Object[] params = {title};
   PreparedStatement pstmt = db.getPstmt(conn, sql, params);
   ResultSet rs = db.getResultSet(pstmt);
   if(rs != null) {
    rs.next();
    oracle.sql.BLOB blob = ((OracleResultSet)rs).getBLOB("text");
    byte[] bytes = new byte[(int) blob.length()];
    InputStream in = blob.getBinaryStream();
    in.read(bytes);
    tg = new TongGao();
    tg.setTitle(rs.getString("title"));
    tg.setText(new String(bytes, "GBK"));//这里的编码要和数据库里的一样才可以
    tg.setIssuedate(rs.getDate("issuedate").toString());
    tg.setEnddate(rs.getDate("enddate").toString());
    tg.setCategory(rs.getString("category"));
    tg.setDepartment(rs.getString("department"));
    tg.setPublisher(rs.getString("publisher"));
    tg.setTop(rs.getString("top"));
    tg.setStatus(rs.getString("status"));
    tg.setBz(rs.getString("bz"));
    tg.setFiles(this.getFiles(rs.getString("filelinks")));
    in.close();
   }
   conn.commit();
   conn.setAutoCommit(true);
   rs.close();
   pstmt.close();
  } catch (SQLException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } catch (UnsupportedEncodingException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    e1.printStackTrace();
   }
   e.printStackTrace();
  } catch (IOException e) {
   try {
    conn.rollback();
   } catch (SQLException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
   }
   e.printStackTrace();
  } finally {
   db.close(conn);
  }
  return tg;
 }

其中包含的一些公共的方法：

public Connection getConn() {
  Connection conn = null;
  try {
   Class.forName("oracle.jdbc.driver.OracleDriver");
   String url = "jdbc:oracle:thin:@202.206.196.109:1521:orcl";
   String username = "*****";
   String password = "******l";
   conn = DriverManager.getConnection(url, username, password);
  } catch (ClassNotFoundException e) {
   e.printStackTrace();
  } catch (SQLException e) {
   e.printStackTrace();
  }
  return conn;
 }
public PreparedStatement getPstmt(Connection conn, String sql, Object[] params) {
  PreparedStatement pstmt = null;
  if(sql != null && !sql.equals("")) {
   if(params == null || params.length == 0) {
    params = new Object[0];
   }
   try {
    pstmt = conn.prepareStatement(sql);
    for(int i=0;i<params.length;i++) {
     pstmt.setObject((i+1), params[i]);
    }
    pstmt.execute();
   } catch (SQLException e) {
    e.printStackTrace();
   }
  }
  return pstmt;
 }
 
 public ResultSet getResultSet(PreparedStatement pstmt) throws SQLException {
  return pstmt.getResultSet();
 }
 
 public int getCount(PreparedStatement pstmt) throws SQLException {
  return pstmt.getUpdateCount();
 }
 
 public void close(Connection conn) {
  if(conn != null) {
   try {
    conn.close();
   } catch (SQLException e) {
    e.printStackTrace();
   }
   conn = null;
  }
 }

有不对的地方请大家指点，这些代码在我这运行着可以，应该没有问题，希望能帮到一些人（刚弄blob的）~