| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.empire.db.expr.compare; |
| |
| import java.util.Set; |
| |
| import org.apache.empire.commons.ObjectUtils; |
| import org.apache.empire.db.DBColumn; |
| import org.apache.empire.db.DBCommand; |
| import org.apache.empire.db.DBDatabase; |
| import org.apache.empire.db.DBSQLBuilder; |
| |
| |
| /** |
| * This class is used for combining two filter constraints by and / or operator<br> |
| * <P> |
| * There is no need to explicitly create instances of this class.<BR> |
| * Instead use {@link DBCompareExpr#and(DBCompareExpr)} or {@link DBCompareExpr#or(DBCompareExpr)} |
| * <P> |
| * |
| */ |
| public class DBCompareAndOrExpr extends DBCompareExpr |
| { |
| // *Deprecated* private static final long serialVersionUID = 1L; |
| |
| protected final DBCompareExpr left; |
| protected final DBCompareExpr right; |
| protected final boolean or; |
| |
| /** |
| * Constructs a DBCompareColExpr object |
| * |
| * @param left the left side of the expression |
| * @param right the right side of the expression |
| * @param or true for OR operation, false for AND |
| */ |
| public DBCompareAndOrExpr(DBCompareExpr left, DBCompareExpr right, boolean or) |
| { |
| this.left = left; |
| this.right = right; |
| this.or = or; |
| } |
| |
| public DBCompareExpr getLeft() |
| { |
| return left; |
| } |
| |
| public DBCompareExpr getRight() |
| { |
| return right; |
| } |
| |
| public boolean isOr() |
| { |
| return or; |
| } |
| |
| /** |
| * Returns the current DBDatabase object. |
| * |
| * @return the current DBDatabase object |
| */ |
| @SuppressWarnings("unchecked") |
| @Override |
| public final DBDatabase getDatabase() |
| { |
| return left.getDatabase(); |
| } |
| |
| /** |
| * Prepare function |
| * @param cmd |
| */ |
| @Override |
| public void prepareCommand(DBCommand cmd) |
| { |
| left.prepareCommand(cmd); |
| right.prepareCommand(cmd); |
| } |
| |
| /** |
| * Copy Command |
| * @param cmd |
| */ |
| @Override |
| public DBCompareExpr copy(DBCommand newCmd) |
| { |
| return new DBCompareAndOrExpr(left.copy(newCmd), right.copy(newCmd), or); |
| } |
| |
| /** |
| * @see org.apache.empire.db.DBExpr#addReferencedColumns(Set) |
| */ |
| @Override |
| public void addReferencedColumns(Set<DBColumn> list) |
| { // return all Columns |
| left.addReferencedColumns(list); |
| right.addReferencedColumns(list); |
| } |
| |
| /** |
| * Creates the SQL-Command sets the specified compare value |
| * (the varible boolOP) between the two DBCompareExpr objects. |
| * |
| * @param sql the SQL statment |
| * @param context the current SQL-Command context |
| */ |
| @Override |
| public void addSQL(DBSQLBuilder sql, long context) |
| { |
| // Name or Value Only ? |
| if ((context & CTX_NAME )==0 || |
| (context & CTX_VALUE)==0) |
| { // add both values separated by "," |
| left.addSQL(sql, context); |
| sql.append(","); |
| right.addSQL(sql, context); |
| return; |
| } |
| // Parenthesis |
| boolean parenthesis = ((context & CTX_NOPARENTHESES) == 0) && or; |
| boolean nested = ((left instanceof DBCompareAndOrExpr) && ((DBCompareAndOrExpr)left).or==false); |
| if (parenthesis) |
| sql.append("("); |
| if (parenthesis && nested) |
| sql.append("("); |
| // the left expression |
| left.addSQL(sql, context); |
| // Parenthesis |
| if (parenthesis && nested) |
| sql.append(")"); |
| // Combine operator |
| sql.append((or ? " OR " : " AND ")); |
| // Parenthesis |
| nested = ((right instanceof DBCompareAndOrExpr) && ((DBCompareAndOrExpr)right).or==false); |
| if (parenthesis && nested) |
| sql.append("("); |
| // the right expression |
| right.addSQL(sql, context); |
| if (parenthesis && nested) |
| sql.append(")"); |
| // Parenthesis |
| if (parenthesis) |
| sql.append(")"); |
| } |
| |
| /** |
| * Returns the subquery params if the two expressions to be combined |
| * @return the subquery params or null |
| @Override |
| public Object[] getSubqueryParams() |
| { |
| Object[] lParams = left.getSubqueryParams(); |
| Object[] rParams = right.getSubqueryParams(); |
| return ObjectUtils.combine(lParams, rParams); |
| } |
| */ |
| |
| /** |
| * Returns whether the constraint should replace another one or not. |
| * |
| * @return true it the constraints are mutually exclusive or false otherwise |
| */ |
| @Override |
| public boolean isMutuallyExclusive(DBCompareExpr other) |
| { |
| if (ObjectUtils.isWrapper(other)) |
| { // unwrap |
| other = ObjectUtils.unwrap(other); |
| } |
| if (other instanceof DBCompareAndOrExpr) |
| { // check other |
| DBCompareAndOrExpr otherExpr = (DBCompareAndOrExpr)other; |
| if (left .isMutuallyExclusive(otherExpr.left) && |
| right.isMutuallyExclusive(otherExpr.right)) |
| return (this.or==otherExpr.or); |
| } |
| return false; |
| } |
| |
| /** |
| * wraps the current expression with parenthesis. |
| * |
| * @return the new DBCompareColExpr object |
| */ |
| public DBCompareExpr parenthesis() |
| { |
| // create parenthesis Expression |
| return new DBCompareParenthesisExpr(this); |
| } |
| |
| } |