JAVA数据库处理(连接,数据查询,结果集返回)
package john import java.io.IOException; import java.util.*; public class QueryDataRow { public HashMap hashColumn; private String[] data; public QueryDataRow() { super(); } public String get(String str) throws IOException { int colindex = ((Integer) (hashColumn.get(str))).intValue(); return DBUtil.deTransSql(data[colindex]); } public void setData(String[] s) { this.data = new String[s.length]; for (int i = 0; i < s.length; i++) { this.data[i] = s[i]; } } public void resetColumn(String columnName, String columnValue) { int colindex = ((Integer) (hashColumn.get(columnName))).intValue(); data[colindex] = columnValue; } }
package john import java.util.*; import java.sql.*; public class QueryData { private ArrayList rows; public QueryData() { rows = new ArrayList(); rows.clear(); } public boolean setData(ResultSet rs) throws Exception { boolean ret = false; try { ResultSetMetaData rsdata = rs.getMetaData(); int ColumnCount = rsdata.getColumnCount(); String Columns[] = new String[ColumnCount]; HashMap hashColumn = new HashMap(); for (int i = 0; i < ColumnCount; i++) { Columns[i] = rsdata.getColumnName(i + 1); hashColumn.put(Columns[i], new Integer(i)); } while (rs.next()) { String rowdata[] = new String[ColumnCount]; for (int i = 0; i < ColumnCount; i++) { String column = Columns[i]; String value = rs.getString(column); value = (value != null ? value : ""); rowdata[i] = value; } QueryDataRow row = new QueryDataRow(); row.hashColumn = hashColumn; row.setData(rowdata); rows.add(row); } ret = true; } catch (Exception e) { ret = false; throw e; } return ret; } public boolean removeRow(int index) throws Exception { try { if (rows != null) { rows.remove(index); return true; } else { return false; } } catch (Exception ex) { throw ex; } } public QueryDataRow getRow(int index) throws Exception { try { if (rows != null) { QueryDataRow row = new QueryDataRow(); return (QueryDataRow) rows.get(index); } else { return null; } } catch (Exception ex) { throw ex; } } public int size() { if (rows != null) { return rows.size(); } else { return 0; } } }
package john import java.io.IOException; import java.sql.*; import javax.sql.*; public class DBUtil { public static final String STRING = "0"; public static final String DATE = "1"; public static final String INT = "2"; private Connection conn = null; //DB接続 private ResultSet sqlResult = null; private DataSource ds = null; Statement sqlStatement = null; /* エラー情報*/ public String errStr = null; private static Logger logger = Logger.getLogger(DBUtil.class.getName()); static { try { Class.forName("oracle.jdbc.driver.OracleDriver"); } catch (Exception ex) { ex.printStackTrace(); } } public DBUtil(Connection pConn) { conn = pConn; //DB接続 sqlResult = null; ds = null; sqlStatement = null; errStr = new String(""); } public Connection connOpen() throws Exception { try { if (Common.CONN_FLAG == true) { String strDbIp = Common.getData("other.dbhost"); String strDbPort = Common.getData("other.dbport"); String strDbName = Common.getData("other.dbname"); String strUsername = Common.getData("other.dbuser"); String strPassword = Common.getData("other.dbpswd"); String strDBUrl = "jdbc:oracle:thin:@"+strDbIp+":"+strDbPort+":"+strDbName; conn = DriverManager.getConnection(strDBUrl, strUsername, strPassword); } conn.setAutoCommit(false); sqlStatement = null; sqlStatement = conn.createStatement(); return conn; } catch (SQLException e) { String strErr = "SQL connection error: /n" + e.getMessage(); logger.error("DBUTIL",strErr); this.errStr += strErr; throw new BaseException("syserr"); } } public void connClose() throws Exception { try { if(sqlStatement != null) sqlStatement.close(); sqlStatement = null; if(conn != null) if(!conn.isClosed()) conn.close(); conn = null; } catch (SQLException ex) { logger.error("DBUTIL",ex.getMessage()); logger.error("DBUTIL","DB closing exception!"); throw new BaseException("syserr"); } } public QueryData selQuery(String strQuerySQL) throws Exception { try { QueryData qd = new QueryData(); Statement tmpSQLStatement = conn.createStatement(); tmpSQLStatement.execute(transSql(strQuerySQL)); sqlResult = null; sqlResult = tmpSQLStatement.getResultSet(); qd.setData(sqlResult); if(sqlResult != null) sqlResult.close(); sqlResult = null; tmpSQLStatement.close(); tmpSQLStatement = null; logger.error("DBUTIL",strQuerySQL); return qd; } catch(Exception e) { logger.error("DBUTIL","SQL error: " + strQuerySQL); logger.error("DBUTIL",e.getMessage()); throw new BaseException("syserr"); } finally { } } public QueryData selQureyPrep(String pQuerySql,String[][] conditionlist) throws Exception { try { QueryData qd = new QueryData(); PreparedStatement prep = conn.prepareStatement(transSql(pQuerySql)); int cnt = 0; for (int x = 0; x < conditionlist.length;x++) { boolean isFalse = true; while (isFalse) { int mode = 0; String strMode =conditionlist[x][0]; if (!Common.checkNull(strMode)) { isFalse = false; break; } else { cnt++; mode = Integer.parseInt(strMode); } switch (mode) { case 0: prep.setString(cnt,String.valueOf(conditionlist[x][1])); isFalse = false; break; case 1: prep.setDate(cnt,Date.valueOf(conditionlist[x][1])); isFalse = false; break; case 2: prep.setInt(cnt,Integer.parseInt(conditionlist[x][1])); isFalse = false; break; default : isFalse = false; break; } } } sqlResult = null; sqlResult = prep.executeQuery(); qd.setData(sqlResult); if(sqlResult != null) sqlResult.close(); sqlResult = null; prep.close(); prep = null; logger.error("DBUTIL",pQuerySql); return qd; } catch(Exception e) { logger.error("DBUTIL","SQL error: " + pQuerySql); logger.error("DBUTIL",e.getMessage()); throw new BaseException("syserr"); } finally { } } public ResultSet selQuery_large(String strQuerySQL) throws Exception { try { sqlStatement.execute(transSql(strQuerySQL)); sqlResult = sqlStatement.getResultSet(); logger.error("DBUTIL",strQuerySQL); return sqlResult; } catch(SQLException e) { logger.error("DBUTIL","SQL error: " + strQuerySQL); logger.error("DBUTIL",e.getMessage()); throw new BaseException("syserr"); } finally { } } public void doQuery(String strQuerySQL) throws Exception { try { Statement SQLStatement = conn.createStatement(); SQLStatement.executeUpdate(transSql(strQuerySQL)); logger.error("DBUTIL",strQuerySQL); SQLStatement.close(); SQLStatement = null; } catch(SQLException e) { logger.error("DBUTIL","SQL error: " + strQuerySQL); logger.error("DBUTIL",e.getMessage()); throw new BaseException("syserr"); } finally { } } public void doQueryPrep(String pQuerySql,String[][] conditionlist) throws Exception { try { PreparedStatement prep = conn.prepareStatement(transSql(pQuerySql)); int cnt = 0; for (int x = 0; x < conditionlist.length;x++){ boolean isFalse = true; while (isFalse){ int mode = 0; String strMode =conditionlist[x][0]; if (!Common.checkNull(strMode)){ isFalse = false; break; }else{ cnt++; mode = Integer.parseInt(strMode); } switch (mode) { case 0: prep.setString(cnt,String.valueOf(conditionlist[x][1])); isFalse = false; break; case 1: prep.setDate(cnt,Date.valueOf(conditionlist[x][1])); isFalse = false; break; case 2: prep.setInt(cnt,Integer.parseInt(conditionlist[x][1])); isFalse = false; break; default : isFalse = false; break; } } } prep.executeUpdate(); logger.error("DBUTIL","SQL error: " + pQuerySql); prep.close(); prep = null; } catch(SQLException e) { logger.error("DBUTIL","SQL error: " + pQuerySql); logger.error("DBUTIL",e.getMessage()); throw new BaseException("syserr"); } finally { } } public boolean doCommit() throws Exception { try { conn.commit(); return true; } catch (SQLException e) { logger.error("DBUTIL","SQL commit error! "); logger.error("DBUTIL",e.getMessage()); conn.rollback(); throw new BaseException("syserr"); } finally { } } public void doRollback() throws Exception { try { if(conn != null) conn.rollback(); } catch (Exception e) { logger.error("DBUTIL","SQL rollback error! " ); logger.error("DBUTIL",e.getMessage()); } } public static String transSql(String strInput) throws IOException { String strOutput = strInput; //return EucJpFile.toJIS(strOutput); return strOutput; } public static String deTransSql(String strInput) throws IOException { String strOutput = strInput; return strOutput; //return EucJpFile.toCp932(strOutput); } }
以下是JAVA对DB操作的一种实现方式,与大家一起共享,对初学者可能有一定的帮助,当然对高手而 言,用处就不见的大了,欢迎大家提出更好的意见和建议.为了商业规则,代码的注释去掉了,请大家见谅.