com.blazebit.persistence.criteria.impl.expression.function.CoalesceFunction Maven / Gradle / Ivy
/*
* Copyright 2014 - 2021 Blazebit.
*
* Licensed 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 com.blazebit.persistence.criteria.impl.expression.function;
import com.blazebit.persistence.criteria.impl.BlazeCriteriaBuilderImpl;
import com.blazebit.persistence.criteria.impl.ParameterVisitor;
import com.blazebit.persistence.criteria.impl.RenderContext;
import com.blazebit.persistence.criteria.impl.expression.AbstractExpression;
import com.blazebit.persistence.criteria.impl.expression.LiteralExpression;
import javax.persistence.criteria.CriteriaBuilder.Coalesce;
import javax.persistence.criteria.Expression;
import java.util.ArrayList;
import java.util.List;
/**
* @author Christian Beikov
* @since 1.2.0
*/
public class CoalesceFunction extends AbstractExpression implements Coalesce {
private static final long serialVersionUID = 1L;
private final List> expressions;
private Class javaType;
public CoalesceFunction(BlazeCriteriaBuilderImpl criteriaBuilder, Class javaType) {
super(criteriaBuilder, javaType);
this.javaType = javaType;
this.expressions = new ArrayList>();
}
@Override
public Class getJavaType() {
return javaType;
}
@Override
public Coalesce value(T value) {
return value(new LiteralExpression(criteriaBuilder, value));
}
@Override
@SuppressWarnings({"unchecked"})
public Coalesce value(Expression value) {
expressions.add(value);
if (javaType == null) {
javaType = (Class) value.getJavaType();
}
return this;
}
public List> getExpressions() {
return expressions;
}
@Override
public void visitParameters(ParameterVisitor visitor) {
for (Expression expr : getExpressions()) {
visitor.visit(expr);
}
}
@Override
public void render(RenderContext context) {
final List> exprs = getExpressions();
final StringBuilder buffer = context.getBuffer();
buffer.append("COALESCE(");
for (int i = 0; i < exprs.size(); i++) {
if (i != 0) {
buffer.append(',');
}
context.apply(exprs.get(i));
}
buffer.append(')');
}
}