Java tutorial
/* * Copyright 2016 King's College London, Richard Jackson <richgjackson@gmail.com>. * * 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 uk.ac.kcl.itemProcessors; import org.slf4j.LoggerFactory; import org.springframework.batch.item.ItemProcessor; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Value; import org.springframework.context.annotation.ComponentScan; import org.springframework.context.annotation.Profile; import org.springframework.core.env.Environment; import org.springframework.http.client.SimpleClientHttpRequestFactory; import org.springframework.retry.RecoveryCallback; import org.springframework.retry.RetryCallback; import org.springframework.retry.RetryContext; import org.springframework.retry.backoff.FixedBackOffPolicy; import org.springframework.retry.policy.TimeoutRetryPolicy; import org.springframework.retry.support.RetryTemplate; import org.springframework.stereotype.Service; import org.springframework.web.client.RestTemplate; import uk.ac.kcl.exception.WebserviceProcessingFailedException; import uk.ac.kcl.model.Document; import javax.annotation.PostConstruct; import java.util.*; @Profile("webservice") @Service("webserviceDocumentItemProcessor") @ComponentScan("uk.ac.kcl.service") public class WebserviceDocumentItemProcessor implements ItemProcessor<Document, Document> { private static final org.slf4j.Logger LOG = LoggerFactory.getLogger(WebserviceDocumentItemProcessor.class); @Autowired private Environment env; @Value("${webservice.endPoint}") private String endPoint; @Value("${webservice.fieldName}") private String fieldName; @Value("${webservice.connectTimeout}") private int connectTimeout; @Value("${webservice.readTimeout}") private int readTimeout; @Value("${webservice.name}") private String webserviceName; private RetryTemplate retryTemplate; private RestTemplate restTemplate; private List<String> fieldsToSendToWebservice; @PostConstruct private void init() { fieldsToSendToWebservice = Arrays .asList(env.getProperty("webservice.fieldsToSendToWebservice").toLowerCase().split(",")); setFieldName(fieldName); this.retryTemplate = getRetryTemplate(); this.restTemplate = new RestTemplate(); ((SimpleClientHttpRequestFactory) restTemplate.getRequestFactory()).setReadTimeout(readTimeout); ((SimpleClientHttpRequestFactory) restTemplate.getRequestFactory()).setConnectTimeout(connectTimeout); } public void setFieldsToSendToWebservice(List<String> fields) { this.fieldsToSendToWebservice = fields; } @Override public Document process(final Document doc) { LOG.debug("starting " + this.getClass().getSimpleName() + " on doc " + doc.getDocName()); executeWithRetryIgnoringExceptions(doc); LOG.debug("finished " + this.getClass().getSimpleName() + " on doc " + doc.getDocName()); return doc; } public void setFieldName(String fieldName) { this.fieldName = fieldName; } private RetryTemplate getRetryTemplate() { TimeoutRetryPolicy retryPolicy = new TimeoutRetryPolicy(); retryPolicy.setTimeout(Long.valueOf(env.getProperty("webservice.retryTimeout"))); FixedBackOffPolicy backOffPolicy = new FixedBackOffPolicy(); backOffPolicy.setBackOffPeriod(Long.valueOf(env.getProperty("webservice.retryBackoff"))); RetryTemplate template = new RetryTemplate(); template.setRetryPolicy(retryPolicy); template.setBackOffPolicy(backOffPolicy); return template; } //not currently used but migh go back to this method private Document executeWithRetryThrowingExceptions(Document doc) { HashMap<String, Object> newMap = new HashMap<>(); newMap.putAll(doc.getAssociativeArray()); doc.getAssociativeArray().forEach((k, v) -> { if (fieldsToSendToWebservice.contains(k.toLowerCase())) { Object json = retryTemplate .execute(new RetryCallback<Object, WebserviceProcessingFailedException>() { public Object doWithRetry(RetryContext context) { // business logic here return restTemplate.postForObject(endPoint, v, Object.class); } }, new RecoveryCallback() { @Override public Object recover(RetryContext context) throws WebserviceProcessingFailedException { LOG.warn(webserviceName + " failed on document " + doc.getDocName()); throw new WebserviceProcessingFailedException( webserviceName + " failed on document " + doc.getDocName(), context.getLastThrowable()); } }); newMap.put(fieldName, json); } }); doc.getAssociativeArray().clear(); doc.getAssociativeArray().putAll(newMap); return doc; } private Document executeWithRetryIgnoringExceptions(Document doc) { HashMap<String, Object> newMap = new HashMap<>(); newMap.putAll(doc.getAssociativeArray()); doc.getAssociativeArray().forEach((k, v) -> { if (fieldsToSendToWebservice.contains(k.toLowerCase())) { Object json = retryTemplate .execute(new RetryCallback<Object, WebserviceProcessingFailedException>() { public Object doWithRetry(RetryContext context) { // business logic here Object ob = restTemplate.postForObject(endPoint, v, Object.class); return ob; } }, new RecoveryCallback() { @Override public Object recover(RetryContext context) throws WebserviceProcessingFailedException { LOG.warn(webserviceName + " failed on document " + doc.getDocName()); ArrayList<LinkedHashMap<Object, Object>> al = new ArrayList<LinkedHashMap<Object, Object>>(); LinkedHashMap<Object, Object> hm = new LinkedHashMap<Object, Object>(); hm.put(fieldName, webserviceName + " failed"); al.add(hm); doc.getExceptions().add(new WebserviceProcessingFailedException( webserviceName + " failed on document " + doc.getDocName())); return al; } }); newMap.put(fieldName, json); } }); doc.getAssociativeArray().clear(); doc.getAssociativeArray().putAll(newMap); return doc; } }