Java tutorial
// // Licensed to the Apache Software Foundation (ASF) under one // or more contributor license agreements. See the NOTICE file // distributed with this work for additional information // regarding copyright ownership. The ASF licenses this file // to you 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.cloud.utils.rest; import java.io.IOException; import java.net.URI; import org.apache.http.HttpHost; import org.apache.http.client.methods.CloseableHttpResponse; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.log4j.Logger; public class BasicRestClient implements RestClient { private static final Logger s_logger = Logger.getLogger(BasicRestClient.class); private static final String HTTPS = HttpConstants.HTTPS; private static final int HTTPS_PORT = HttpConstants.HTTPS_PORT; private final CloseableHttpClient client; private final HttpClientContext clientContext; private BasicRestClient(final Builder<?> builder) { client = builder.client; clientContext = builder.clientContext; clientContext.setTargetHost(buildHttpHost(builder.host)); } protected BasicRestClient(final CloseableHttpClient client, final HttpClientContext clientContex, final String host) { this.client = client; clientContext = clientContex; clientContext.setTargetHost(buildHttpHost(host)); } private static HttpHost buildHttpHost(final String host) { return new HttpHost(host, HTTPS_PORT, HTTPS); } @SuppressWarnings("rawtypes") public static Builder create() { return new Builder(); } @Override public CloseableHttpResponse execute(final HttpUriRequest request) throws CloudstackRESTException { logRequestExecution(request); try { return client.execute(clientContext.getTargetHost(), request, clientContext); } catch (final IOException e) { throw new CloudstackRESTException("Could not execute request " + request, e); } } private void logRequestExecution(final HttpUriRequest request) { final URI uri = request.getURI(); String query = uri.getQuery(); query = query != null ? "?" + query : ""; s_logger.debug("Executig " + request.getMethod() + " request on " + clientContext.getTargetHost() + uri.getPath() + query); } @Override public void closeResponse(final CloseableHttpResponse response) throws CloudstackRESTException { try { s_logger.debug("Closing HTTP connection"); response.close(); } catch (final IOException e) { final StringBuilder sb = new StringBuilder(); sb.append("Failed to close response object for request.\nResponse: ").append(response); throw new CloudstackRESTException(sb.toString(), e); } } @SuppressWarnings({ "rawtypes", "unchecked" }) protected static class Builder<T extends Builder> { private CloseableHttpClient client; private HttpClientContext clientContext = HttpClientContext.create(); private String host; public T client(final CloseableHttpClient client) { this.client = client; return (T) this; } public T clientContext(final HttpClientContext clientContext) { this.clientContext = clientContext; return (T) this; } public T host(final String host) { this.host = host; return (T) this; } public BasicRestClient build() { return new BasicRestClient(this); } } }