/*
 * Copyright 2022 Red Hat, Inc. and/or its affiliates.
 *
 * 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 org.kie.kogito.serverless.workflow.utils;

import java.util.Collections;
import java.util.Map;
import java.util.WeakHashMap;

import org.kie.kogito.process.expr.Expression;
import org.kie.kogito.process.expr.ExpressionHandler;

public abstract class CachedExpressionHandler implements ExpressionHandler {

    private Map<String, Expression> expressions = Collections.synchronizedMap(new WeakHashMap<>());

    @Override
    public Expression get(String expr) {
        return expressions.computeIfAbsent(ExpressionHandlerUtils.trimExpr(expr), this::buildExpression);
    }

    protected abstract Expression buildExpression(String expr);
}
