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/** * Copyright 2003 ZhongTian, Inc. All rights reserved. qingdao tec * PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. $Id: DatabaseConnection.java,v 1.2 2006/05/18 08:20:22 wiserd Exp $ * File:DatabaseConnection.java Date Author Changes March 5 2003 wangdeliang * Created */ package skyline.platform.db; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Hashtable; import javax.naming.Context; import javax.naming.InitialContext; import javax.sql.DataSource; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import skyline.platform.deb.BussDebug; import skyline.platform.deb.DebugInfo; import skyline.platform.utils.*; /** * * */ public class DatabaseConnection { private static final Log logger = LogFactory.getLog(DatabaseConnection.class); // protected Exception errorException; /** * Description of the Field */ public final static String DEFAULT_DATASOURCE_URL = "ccb_pool"; private java.sql.Connection connect; /** * (true-,false-) * */ private boolean isAuto = true; /** * ,0 */ private int layers = 0; /** * NoAvailableResourceException * * @exception * * @roseuid 3E5B223E0372 */ public DatabaseConnection() throws Exception { try { Hashtable prop = new Hashtable(); Context initCtx = new InitialContext(prop); DataSource ds = (DataSource) initCtx.lookup(DEFAULT_DATASOURCE_URL); connect = ds.getConnection(); // this.register(); } catch (Exception e) { errorException = e; throw e; } } /** * Constructor for the DatabaseConnection object * * @param sDBDriver * Description of the Parameter * @param sConnStr * Description of the Parameter * @param user * Description of the Parameter * @param passwd * Description of the Parameter * @exception * */ public DatabaseConnection(String sDBDriver, String sConnStr, String user, String passwd) throws Exception { try { Class.forName(sDBDriver).newInstance(); } catch (Exception ex) { errorException = ex; ex.printStackTrace(); } try { connect = DriverManager.getConnection(sConnStr, user, passwd); // this.register(); } catch (SQLException ex) { errorException = ex; ex.printStackTrace(); } } /** * */ public void begin() { /* * isAuto:true,false. isAutofalselayers1 @roseuid * 3E5B22540070 */ isAuto = false; try { if (connect.getAutoCommit()) connect.setAutoCommit(false); } catch (SQLException sqle) { } layers++; } /** * */ public void commit() { /* * layers--,layers0, @roseuid 3E5B22D7024F */ if (!isAuto) { layers--; if (layers == 0) { try { connect.commit(); connect.setAutoCommit(true); isAuto = true; } catch (SQLException sqle) { } } // if } } /** * */ public void rollback() { /* * ,layers = 0 @roseuid 3E5B22E40258 */ if (!isAuto) { layers = 0; try { connect.rollback(); isAuto = true; } catch (java.sql.SQLException sqle) { } } } /** * /** * * @param sql * sql * @return int * @roseuid 3E5B22F70179 */ public int executeUpdate(String sql) { if (sql == null || sql.trim().length() == 0) { logger.error("DatabaseConnection.executeUpdate's sql parameter is null!!!"); return -1000; } // sql printsql(sql); try { Statement st = connect.createStatement(); int result = st.executeUpdate(sql); st.close(); return result; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); if (sqle.getErrorCode() < 0) { return sqle.getErrorCode(); } else { return sqle.getErrorCode() * (-1); } } } /** * sql * * @param sql * @return com.zt.db.RecordSet * @roseuid 3E5B230E0281 */ public RecordSet executeQuery(String sql) { if (sql == null || sql.trim().length() == 0) { logger.error("DatabaseConnection.executeQuery's sql parameter is null!!!"); return null; } printsql(sql); try { Statement st = connect.createStatement(); ResultSet rs = st.executeQuery(sql); RecordSet records = new RecordSet(rs); rs.close(); st.close(); return records; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); return null; } } public ResultSet executeResultSetQuery(String sql) { if (sql == null || sql.trim().length() == 0) { logger.error("DatabaseConnection.executeQuery's sql parameter is null!!!"); return null; } //sql printsql(sql); try { Statement st = connect.createStatement(); ResultSet rs = st.executeQuery(sql); return rs; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); return null; } } /** * Description of the Method * * @param sql * Description of the Parameter * @param beginIndex * Description of the Parameter * @param resultNo * Description of the Parameter * @return Description of the Return Value */ public RecordSet executeQuery(String sql, int beginIndex, int resultNo) { if (sql == null || sql.trim().length() == 0) { logger.error("DatabaseConnection.executeQuery's sql parameter is null!!!"); return new RecordSet(); } //sql printsql(sql); try { String pageSql = ""; Statement st = connect.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY); if (Basic.getDbType().equals("DB2")) { pageSql = " select * from (SELECT ta.*, ROWNUMBER() OVER () rn FROM ( " + sql + ") ta FETCH FIRST " + (beginIndex - 1 + resultNo) + " ROW ONLY) tb where tb.rn>" + (beginIndex - 1); } else pageSql = " select * from ( select t1.*, rownum rnum from ( " + sql + " ) t1 where rownum<= " + (beginIndex - 1 + resultNo) + " ) t2 where t2.rnum> " + (beginIndex - 1); // sql printsql("page sql:" + pageSql); ResultSet rs = st.executeQuery(pageSql); RecordSet records = new RecordSet(rs); rs.close(); st.close(); return records; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); return new RecordSet(); } } /** * * * @return boolean * @roseuid 3E5B244903E2 */ public boolean isAuto() { return isAuto; } /** * * * @param isAuto * boolean * @roseuid 3E5EA680009C */ public void setAuto(boolean isAuto) { try { connect.setAutoCommit(isAuto); } catch (SQLException sqle) { errorException = sqle; } this.isAuto = isAuto; } /** * ,, * * @roseuid 3E5B3532018E */ public void close() { try { connect.close(); // this.remove(); } catch (SQLException ex) { errorException = ex; ex.printStackTrace(); } } /** * Gets the preparedStatement attribute of the DatabaseConnection object * * @param str * Description of the Parameter * @return The preparedStatement value */ public java.sql.PreparedStatement getPreparedStatement(String str) { try { PreparedStatement st = connect.prepareStatement(str, ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_READ_ONLY); return st; } catch (SQLException ex) { errorException = ex; return null; } } /** * Description of the Method * * @param pst * Description of the Parameter * @return Description of the Return Value */ public RecordSet executeQuery(PreparedStatement pst) { if (pst == null) { return new RecordSet(); } try { ResultSet rs = pst.executeQuery(); RecordSet records = new RecordSet(rs); pst.close(); return records; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); return new RecordSet(); } } /** * Description of the Method * * @param pst * Description of the Parameter * @param beginIndex * Description of the Parameter * @param resultNo * Description of the Parameter * @return Description of the Return Value */ public RecordSet executeQuery(PreparedStatement pst, int beginIndex, int resultNo) { if (pst == null) { System.out.println("DatabaseConnection.executeQuery's pst parameter is null!!!"); return new RecordSet(); } try { pst.setMaxRows(beginIndex - 1 + resultNo); ResultSet rs = pst.executeQuery(); if (beginIndex != 1) { rs.absolute(beginIndex - 1); } RecordSet records = new RecordSet(rs, resultNo); rs.close(); pst.close(); return records; } catch (SQLException sqle) { errorException = sqle; logger.error("", sqle); return new RecordSet(); } } /** * Gets the connection attribute of the DatabaseConnection object * * @return The connection value */ public Connection getConnection() { return connect; } public String getErrorMsg() { return ""; } public void setErrorMsg(String errorMsg) { if (errorMsg != null) { if (errorMsg.indexOf("SQL") > 0) { errorMsg = errorMsg.substring(errorMsg.indexOf("SQL"), errorMsg.length()); errorMsg = DBUtil.fromDB(errorMsg); } } } public Exception getErrorException() { return errorException; } private void printsql(String sql) { logger.debug(sql); } // private boolean debug = false; private void register() { if (debug) ConnectionManager.badconn.put(this.hashCode() + "", new DebugInfo(BussDebug.inferCaller())); } private void remove() { if (debug) ConnectionManager.badconn.remove(this.hashCode() + ""); } }