org.apache.openjpa.jdbc.kernel.exps.WhenScalar Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
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* 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
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* KIND, either express or implied. See the License for the
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package org.apache.openjpa.jdbc.kernel.exps;
import java.util.Map;
import org.apache.openjpa.jdbc.sql.SQLBuffer;
import org.apache.openjpa.jdbc.sql.Select;
import org.apache.openjpa.kernel.exps.ExpressionVisitor;
/**
* Value produced by a when_clause of a case expression.
*
* @author Catalina Wei
*/
public class WhenScalar
implements Exp {
private final Val _val1;
private final Val _val2;
/**
* Constructor.
*/
public WhenScalar(Val val1, Val val2) {
_val1 = val1;
_val2 = val2;
}
public Val getVal1() {
return _val1;
}
public Val getVal2() {
return _val2;
}
public Class getType() {
return _val2.getType();
}
public ExpState initialize(Select sel, ExpContext ctx, Map contains) {
ExpState s1 = _val1.initialize(sel, ctx, 0);
ExpState s2 = _val2.initialize(sel, ctx, 0);
return new BinaryOpExpState(sel.and(s1.joins, s2.joins), s1, s2);
}
public void appendTo(Select sel, ExpContext ctx, ExpState state,
SQLBuffer buf) {
BinaryOpExpState bstate = (BinaryOpExpState) state;
_val1.appendTo(sel, ctx, bstate.state1, buf, 0);
buf.append(" THEN ");
_val2.appendTo(sel, ctx, bstate.state2, buf, 0);
}
public void selectColumns(Select sel, ExpContext ctx, ExpState state,
boolean pks) {
BinaryOpExpState bstate = (BinaryOpExpState) state;
_val1.selectColumns(sel, ctx, bstate.state1, pks);
_val2.selectColumns(sel, ctx, bstate.state2, pks);
}
public void acceptVisit(ExpressionVisitor visitor) {
visitor.enter(this);
_val1.acceptVisit(visitor);
_val2.acceptVisit(visitor);
visitor.exit(this);
}
public int getId() {
return Val.WHENSCALAR_VAL;
}
}