org.springframework.batch.item.database.JpaPagingItemReaderAsyncTests.java Source code

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Here is the source code for org.springframework.batch.item.database.JpaPagingItemReaderAsyncTests.java

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/*
 * Copyright 2010-2014 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
 *
 *      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.springframework.batch.item.database;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.Executors;

import javax.persistence.EntityManagerFactory;
import javax.sql.DataSource;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.batch.item.ExecutionContext;
import org.springframework.batch.item.sample.Foo;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.jdbc.JdbcTestUtils;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "JpaPagingItemReaderCommonTests-context.xml")
public class JpaPagingItemReaderAsyncTests {

    /**
     * The number of items to read
     */
    private static final int ITEM_COUNT = 1000;

    /**
     * The number of threads to create
     */
    private static final int THREAD_COUNT = 10;

    private static final int PAGE_SIZE = 10;

    private static Log logger = LogFactory.getLog(JpaPagingItemReaderAsyncTests.class);

    @Autowired
    private DataSource dataSource;

    @Autowired
    private EntityManagerFactory entityManagerFactory;

    private int maxId;

    @Before
    public void init() {
        JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
        maxId = jdbcTemplate.queryForObject("SELECT MAX(ID) from T_FOOS", Integer.class);
        for (int i = ITEM_COUNT; i > maxId; i--) {
            jdbcTemplate.update("INSERT into T_FOOS (ID,NAME,VALUE) values (?, ?, ?)", i, "foo" + i, i);
        }
        assertEquals(ITEM_COUNT, JdbcTestUtils.countRowsInTable(jdbcTemplate, "T_FOOS"));
    }

    @After
    public void destroy() {
        JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
        jdbcTemplate.update("DELETE from T_FOOS where ID>?", maxId);
    }

    @Test
    public void testAsyncReader() throws Throwable {
        List<Throwable> throwables = new ArrayList<Throwable>();
        int max = 10;
        for (int i = 0; i < max; i++) {
            try {
                doTest();
            } catch (Throwable e) {
                throwables.add(e);
            }
        }
        if (!throwables.isEmpty()) {
            throw new IllegalStateException(String.format("Failed %d out of %d", throwables.size(), max),
                    throwables.get(0));
        }
    }

    /**
     * @throws Exception
     * @throws InterruptedException
     * @throws ExecutionException
     */
    private void doTest() throws Exception, InterruptedException, ExecutionException {
        final JpaPagingItemReader<Foo> reader = getItemReader();
        CompletionService<List<Foo>> completionService = new ExecutorCompletionService<List<Foo>>(
                Executors.newFixedThreadPool(THREAD_COUNT));
        for (int i = 0; i < THREAD_COUNT; i++) {
            completionService.submit(new Callable<List<Foo>>() {
                @Override
                public List<Foo> call() throws Exception {
                    List<Foo> list = new ArrayList<Foo>();
                    Foo next = null;
                    do {
                        next = reader.read();
                        Thread.sleep(10L);
                        logger.debug("Reading item: " + next);
                        if (next != null) {
                            list.add(next);
                        }
                    } while (next != null);
                    return list;
                }
            });
        }
        int count = 0;
        Set<Foo> results = new HashSet<Foo>();
        for (int i = 0; i < THREAD_COUNT; i++) {
            List<Foo> items = completionService.take().get();
            count += items.size();
            logger.debug("Finished items count: " + items.size());
            logger.debug("Finished items: " + items);
            assertNotNull(items);
            results.addAll(items);
        }
        assertEquals(ITEM_COUNT, count);
        assertEquals(ITEM_COUNT, results.size());
        reader.close();
    }

    private JpaPagingItemReader<Foo> getItemReader() throws Exception {

        String jpqlQuery = "select f from Foo f";

        JpaPagingItemReader<Foo> reader = new JpaPagingItemReader<Foo>();
        reader.setQueryString(jpqlQuery);
        reader.setEntityManagerFactory(entityManagerFactory);
        reader.setPageSize(PAGE_SIZE);
        reader.afterPropertiesSet();
        reader.setSaveState(false);
        reader.open(new ExecutionContext());

        return reader;
    }

}