org.springframework.integration.handler.advice.SpelExpressionRetryStateGenerator.java Source code

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Here is the source code for org.springframework.integration.handler.advice.SpelExpressionRetryStateGenerator.java

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/*
 * Copyright 2002-2019 the original author or authors.
 *
 * 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
 *
 *      https://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.springframework.integration.handler.advice;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.classify.Classifier;
import org.springframework.expression.Expression;
import org.springframework.expression.spel.standard.SpelExpressionParser;
import org.springframework.expression.spel.support.StandardEvaluationContext;
import org.springframework.integration.expression.ExpressionUtils;
import org.springframework.messaging.Message;
import org.springframework.retry.RetryState;
import org.springframework.retry.support.DefaultRetryState;
import org.springframework.util.Assert;

/**
 * Creates a DefaultRetryState from a {@link Message}.
 * @author Gary Russell
 * @since 2.2
 *
 */
public class SpelExpressionRetryStateGenerator implements RetryStateGenerator, BeanFactoryAware {

    private volatile StandardEvaluationContext evaluationContext;

    private final Expression keyExpression;

    private final Expression forceRefreshExpression;

    private volatile Classifier<? super Throwable, Boolean> classifier;

    public SpelExpressionRetryStateGenerator(String keyExpression) {
        this(keyExpression, null);
    }

    public SpelExpressionRetryStateGenerator(String keyExpression, String forceRefreshExpression) {
        Assert.notNull(keyExpression, "keyExpression must not be null");
        this.keyExpression = new SpelExpressionParser().parseExpression(keyExpression);
        this.evaluationContext = ExpressionUtils.createStandardEvaluationContext();
        if (forceRefreshExpression == null) {
            this.forceRefreshExpression = null;
        } else {
            this.forceRefreshExpression = new SpelExpressionParser().parseExpression(forceRefreshExpression);
        }
    }

    @Override
    public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
        this.evaluationContext = ExpressionUtils.createStandardEvaluationContext(beanFactory);
    }

    public void setClassifier(Classifier<? super Throwable, Boolean> classifier) {
        this.classifier = classifier;
    }

    @Override
    public RetryState determineRetryState(Message<?> message) {
        Boolean forceRefresh = this.forceRefreshExpression == null ? Boolean.FALSE
                : this.forceRefreshExpression.getValue(this.evaluationContext, message, Boolean.class);
        return new DefaultRetryState(this.keyExpression.getValue(this.evaluationContext, message),
                forceRefresh == null ? false : forceRefresh, this.classifier);
    }

}