001// *************************************************************************************************************************** 002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file * 003// * distributed with this work for additional information regarding copyright ownership. The ASF licenses this file * 004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance * 005// * with the License. You may obtain a copy of the License at * 006// * * 007// * http://www.apache.org/licenses/LICENSE-2.0 * 008// * * 009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an * 010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the * 011// * specific language governing permissions and limitations under the License. * 012// *************************************************************************************************************************** 013package org.apache.juneau.dto; 014 015import static org.apache.juneau.internal.IOUtils.*; 016 017import java.sql.*; 018import java.util.*; 019 020import org.apache.juneau.internal.*; 021 022/** 023 * Transforms an SQL {@link ResultSet ResultSet} into a list of maps. 024 * <p> 025 * Loads the entire result set into an in-memory data structure, and then closes the result set object. 026 */ 027public final class ResultSetList extends LinkedList<Map<String,Object>> { 028 029 private static final long serialVersionUID = 1L; 030 031 /** 032 * Constructor. 033 * 034 * @param rs The result set to load into this DTO. 035 * @param pos The start position (zero-indexed). 036 * @param limit The maximum number of rows to retrieve. 037 * @param includeRowNums Make the first column be the row number. 038 * @throws SQLException Database error. 039 */ 040 public ResultSetList(ResultSet rs, int pos, int limit, boolean includeRowNums) throws SQLException { 041 try { 042 int rowNum = pos; 043 044 // Get the column names. 045 ResultSetMetaData rsmd = rs.getMetaData(); 046 int offset = (includeRowNums ? 1 : 0); 047 int cc = rsmd.getColumnCount(); 048 String[] columns = new String[cc + offset]; 049 if (includeRowNums) 050 columns[0] = "ROW"; 051 int[] colTypes = new int[cc]; 052 053 for (int i = 0; i < cc; i++) { 054 columns[i+offset] = rsmd.getColumnName(i+1); 055 colTypes[i] = rsmd.getColumnType(i+1); 056 } 057 058 while (--pos > 0 && rs.next()) {} 059 060 // Get the rows. 061 while (limit-- > 0 && rs.next()) { 062 Object[] row = new Object[cc + offset]; 063 if (includeRowNums) 064 row[0] = rowNum++; 065 for (int i = 0; i < cc; i++) { 066 Object o = readEntry(rs, i+1, colTypes[i]); 067 row[i+offset] = o; 068 } 069 add(new SimpleMap(columns, row)); 070 } 071 } finally { 072 rs.close(); 073 } 074 } 075 076 /** 077 * Reads the specified column from the current row in the result set. 078 * 079 * <p> 080 * Subclasses can override this method to handle specific data types in special ways. 081 * 082 * @param rs The result set to read from. 083 * @param col The column number (indexed by 1). 084 * @param dataType The {@link Types type} of the entry. 085 * @return The entry as an Object. 086 */ 087 protected static Object readEntry(ResultSet rs, int col, int dataType) { 088 try { 089 switch (dataType) { 090 case Types.BLOB: 091 Blob b = rs.getBlob(col); 092 return "blob["+b.length()+"]"; 093 case Types.CLOB: 094 Clob c = rs.getClob(col); 095 return "clob["+c.length()+"]"; 096 case Types.LONGVARBINARY: 097 return "longvarbinary["+count(rs.getBinaryStream(col))+"]"; 098 case Types.LONGVARCHAR: 099 return "longvarchar["+count(rs.getAsciiStream(col))+"]"; 100 case Types.LONGNVARCHAR: 101 return "longnvarchar["+count(rs.getCharacterStream(col))+"]"; 102 case Types.TIMESTAMP: 103 return rs.getTimestamp(col); // Oracle returns com.oracle.TIMESTAMP objects from getObject() which isn't a Timestamp. 104 default: 105 return rs.getObject(col); 106 } 107 } catch (Exception e) { 108 return e.getLocalizedMessage(); 109 } 110 } 111}