JDBC連接泄漏

Question

我目前在我的代碼（Java，Struts）中面臨連接泄漏問題。我已經關閉了所有方法的所有結果集，準備好的語句，可調用語句和連接。我仍然面臨這個問題。附加信息是，我正在使用StructDescriptor.createDescriptor來創建oracle對象。它會導致任何連接泄漏？請指教。

代碼如下

  public boolean updatedDetails(Distribution distribution, String appCode, Connection dbConnection) { 
    boolean savedFlag = true; 
    CallableStatement updateStoredProc = null; 
    PreparedStatement pstmt1 = null; 
    try { 
     logger.debug("In DistributionDAO.updatedDistributionDetails"); 
     //PreparedStatement pstmt1 = null; 
     ARRAY liArray = null; 
     ARRAY conArray = null; 
     ARRAY payArray = null; 
    ArrayDescriptor licenseeArrDesc = ArrayDescriptor.createDescriptor(LICENSEE_TAB, dbConnection); 
     ArrayDescriptor contractArrDesc = ArrayDescriptor.createDescriptor(DISTRIBUTION_CONTRACT_TAB, dbConnection); 
     ArrayDescriptor paymentArrDesc = ArrayDescriptor.createDescriptor(DISTRIBUTION_PAYMENT_TAB, dbConnection); 
     licenseeArray = new ARRAY(licenseeArrDesc, dbConnection, licenseeEleList.toArray()); 
      contractArray = new ARRAY(contractArrDesc, dbConnection, contractEleList.toArray()); 
      paymentArray = new ARRAY(paymentArrDesc, dbConnection, paymentEleList.toArray());   
      updateStoredProc = dbConnection.prepareCall("{CALL DIS_UPDATE_PROC(?,?,to_clob(?),?,?,?,?)}"); 
      updateStoredProc.setLong(1, distribution.getDistributionId()); 
      updateStoredProc.setString(2, distribution.getId()); 
      updateStoredProc.setString(3, distribution.getNotes()); 
      updateStoredProc.setString(4, distribution.getNotesUpdateFlag()); 
      updateStoredProc.setArray(5, liArray); 
      updateStoredProc.setArray(6, conArray); 
      updateStoredProc.setArray(7, payArray); 
      String sql1="Update STORY set LAST_UPDATE_DATE_TIME= sysdate WHERE STORY_ID = ? "; 
      pstmt1=dbConnection.prepareStatement(sql1); 
      pstmt1.setLong(1,distribution.getStoryId()); 
      pstmt1.execute(); 
      List<Object> removedEleList = new ArrayList<Object>(); 
      removedEleList.add(createDeleteElementObject(removedEle, dbConnection)); 
      catch (SQLException sqle) { 
     savedFlag = false; 

    } catch (Exception e) { 
     savedFlag = false; 

    } finally { 
     try { 
      updateStoredProc.close(); 
      updateStoredProc = null;    
      pstmt1.close(); 
      pstmt1 = null;  
      dbConnection.close(); 
     } catch (SQLException e) { 

     } 
    } 
    return savedFlag; 
} 




// Method createDeleteElementObject 
private Object createDeleteElementObject(String removedEle, 
     Connection connection) { 

    StructDescriptor structDesc; 
    STRUCT structObj = null; 
    try { 
     structDesc = StructDescriptor.createDescriptor(DISTRIBUTION_REMOVED_ELEMENT_OBJ, connection); 
     if(removedEle != null) { 
      String[] tmpArr = removedEle.split("\\|"); 
      if(tmpArr.length == 2) { 
       Object[] obj = new Object[2]; 
       String eleType = tmpArr[0]; 
       long eleId = Integer.parseInt(tmpArr[1]); 
       obj[0] = eleType.toUpperCase(); 
       obj[1] = eleId; 
       structObj = new STRUCT(structDesc, connection, obj); 
      } 
     } 
    } catch (ArrayIndexOutOfBoundsException e) { 

    } catch (NumberFormatException e) { 

    } catch (SQLException e) { 

    } 

    return structObj; 
}  

Answer 1

一些提示代碼：

你傳遞一個Connection變量到您的電話，但關閉它你的電話裏面 - 是主叫方知道這個事實？讓你的代碼或返回內部的連接也未關閉（調用方法負責），這將是清潔

例外是爲了被抓，不會被忽略 - 你不登錄你的例外 - 你會永遠不知道會發生什麼我敢打賭，您的catch塊中的簡單e.printStackTrace()將顯示有用的信息。

使用try-with-resource（見this post）

//Resources declared in try-with-resource will be closed automatically. 
try(Connection con = getConnection(); 
    PreparedStatement ps = con.prepareStatement(sql)) { 

    //Process Statement... 

} catch(SQLException e) { 
    e.printStackTrace(); 
} 

至少，把每一個接近單一的try-catch裏面：

} finally { 
    try { 
     if(updateStoredProc != null) { 
      updateStoredProc.close(); 
     }   
    } catch (SQLException e) { 
     e.printStackTrace(); 
    } 
    try { 
     if(pstmt1!= null) { 
      pstmt1.close(); 
     }   
    } catch (SQLException e) { 
     e.printStackTrace(); 
    } 
    try { 
     if(dbConnection != null) { 
      dbConnection.close(); 
     }   
    } catch (SQLException e) { 
     e.printStackTrace(); 
    } 
    }