/*
* Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
* Version 1.0, and under the Eclipse Public License, Version 1.0
* (http://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.jaqu.bytecode;
import org.h2.jaqu.Query;
import org.h2.jaqu.SQLStatement;
import org.h2.jaqu.Token;
/**
* A conditional expression.
*/
public class CaseWhen implements Token {
private final Token condition, ifTrue, ifFalse;
private CaseWhen(Token condition, Token ifTrue, Token ifFalse) {
this.condition = condition;
this.ifTrue = ifTrue;
this.ifFalse = ifFalse;
}
static Token get(Token condition, Token ifTrue, Token ifFalse) {
if ("0".equals(ifTrue.toString()) && "1".equals(ifFalse.toString())) {
return Not.get(condition);
} else if ("1".equals(ifTrue.toString()) && "0".equals(ifFalse.toString())) {
return condition;
} else if ("0".equals(ifTrue.toString())) {
return And.get(Not.get(condition), ifFalse);
}
return new CaseWhen(condition, ifTrue, ifFalse);
}
public String toString() {
return "CASEWHEN(" + condition + ", " + ifTrue + ", " + ifFalse + ")";
}
public <T> void appendSQL(SQLStatement stat, Query<T> query) {
stat.appendSQL("CASEWHEN ");
condition.appendSQL(stat, query);
stat.appendSQL(" THEN ");
ifTrue.appendSQL(stat, query);
stat.appendSQL(" ELSE ");
ifFalse.appendSQL(stat, query);
stat.appendSQL(" END");
}
}