com.blazebit.persistence.impl.function.nullfn.NullfnFunction Maven / Gradle / Ivy

/*
 * Copyright 2014 - 2020 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.impl.function.nullfn;

import com.blazebit.persistence.impl.util.JpqlFunctionUtil;
import com.blazebit.persistence.spi.FunctionRenderContext;
import com.blazebit.persistence.spi.JpqlFunction;

/**
 *
 * @author Christian Beikov
 * @since 1.4.1
 */
public class NullfnFunction implements JpqlFunction {

    public static final String FUNCTION_NAME = "nullfn";

    @Override
    public boolean hasArguments() {
        return true;
    }

    @Override
    public boolean hasParenthesesIfNoArguments() {
        return true;
    }

    @Override
    public Class getReturnType(Class firstArgumentType) {
        if (firstArgumentType == null) {
            return Integer.class;
        }
        return firstArgumentType;
    }

    @Override
    public void render(FunctionRenderContext functionRenderContext) {
        if (functionRenderContext.getArgumentsSize() > 1) {
            functionRenderContext.addChunk("cast(");
        }
        functionRenderContext.addChunk("null");
        if (functionRenderContext.getArgumentsSize() > 1) {
            functionRenderContext.addChunk(" as ");
            functionRenderContext.addChunk(JpqlFunctionUtil.unquote(functionRenderContext.getArgument(1)));
            functionRenderContext.addChunk(")");
        }
    }

}