001/* 002 * (C) Copyright 2006-2011 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 * Contributors: 017 * Florent Guillaume 018 */ 019package org.nuxeo.ecm.core.storage.sql.jdbc.db; 020 021import java.io.Serializable; 022import java.util.Collections; 023import java.util.LinkedList; 024import java.util.List; 025import java.util.Set; 026 027import org.apache.commons.lang.StringUtils; 028 029/** 030 * An {@code UPDATE} statement. 031 */ 032public class Update implements Serializable { 033 034 private static final long serialVersionUID = 1L; 035 036 protected final Table table; 037 038 protected String newValues; 039 040 protected String[] from; 041 042 protected String where; 043 044 public Update(Table table) { 045 this.table = table; 046 } 047 048 public Table getTable() { 049 return table; 050 } 051 052 public void setNewValues(String newValues) { 053 this.newValues = newValues; 054 } 055 056 /** Alternative to {@link #setNewValues} */ 057 public void setUpdatedColumns(List<Column> columns) { 058 setUpdatedColumns(columns, Collections.<String> emptySet()); 059 } 060 061 /** 062 * Alternative to {@link #setNewValues} 063 * 064 * @param columns the columns 065 * @param deltas which of the columns are delta updates 066 */ 067 public void setUpdatedColumns(List<Column> columns, Set<String> deltas) { 068 List<String> updatedColumns = new LinkedList<String>(); 069 for (Column column : columns) { 070 if (column.isIdentity()) { 071 // identity column is never inserted 072 continue; 073 } 074 String col = column.getQuotedName(); 075 String fvs = column.getFreeVariableSetter(); 076 String update; 077 if (deltas.contains(column.getKey())) { 078 update = col + " = " + col + " + " + fvs; 079 } else { 080 update = col + " = " + fvs; 081 } 082 updatedColumns.add(update); 083 } 084 newValues = StringUtils.join(updatedColumns, ", "); 085 } 086 087 /** 088 * Sets additional table names with which to join for this update. 089 */ 090 public void setFrom(String... from) { 091 this.from = from; 092 } 093 094 public void setWhere(String where) { 095 if (where == null || where.length() == 0) { 096 throw new IllegalArgumentException("unexpected empty WHERE"); 097 } 098 this.where = where; 099 } 100 101 public String getStatement() { 102 StringBuilder buf = new StringBuilder(128); 103 buf.append("UPDATE "); 104 buf.append(table.getQuotedName()); 105 buf.append(" SET "); 106 buf.append(newValues); 107 if (from != null) { 108 buf.append(" FROM "); 109 if (table.getDialect().doesUpdateFromRepeatSelf()) { 110 buf.append(table.getQuotedName()); 111 buf.append(", "); 112 } 113 buf.append(StringUtils.join(from, ", ")); 114 } 115 if (where != null) { 116 buf.append(" WHERE "); 117 buf.append(where); 118 } else { 119 throw new IllegalArgumentException("unexpected empty WHERE"); 120 } 121 return buf.toString(); 122 } 123}