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 org.apache.ivy.util.url; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.URL; import java.net.UnknownHostException; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.List; import java.util.Locale; import org.apache.commons.httpclient.Credentials; import org.apache.commons.httpclient.Header; import org.apache.commons.httpclient.HttpClient; import org.apache.commons.httpclient.HttpException; import org.apache.commons.httpclient.HttpMethodBase; import org.apache.commons.httpclient.HttpStatus; import org.apache.commons.httpclient.MultiThreadedHttpConnectionManager; import org.apache.commons.httpclient.NTCredentials; import org.apache.commons.httpclient.auth.AuthPolicy; import org.apache.commons.httpclient.auth.AuthScheme; import org.apache.commons.httpclient.auth.AuthScope; import org.apache.commons.httpclient.auth.CredentialsNotAvailableException; import org.apache.commons.httpclient.auth.CredentialsProvider; import org.apache.commons.httpclient.methods.GetMethod; import org.apache.commons.httpclient.methods.HeadMethod; import org.apache.commons.httpclient.methods.PutMethod; import org.apache.commons.httpclient.methods.RequestEntity; import org.apache.commons.httpclient.params.HttpMethodParams; import org.apache.ivy.Ivy; import org.apache.ivy.util.CopyProgressListener; import org.apache.ivy.util.FileUtil; import org.apache.ivy.util.HostUtil; import org.apache.ivy.util.Message; /** * */ public class HttpClientHandler extends AbstractURLHandler { private static final SimpleDateFormat LAST_MODIFIED_FORMAT = new SimpleDateFormat("EEE, d MMM yyyy HH:mm:ss z", Locale.US); // proxy configuration: obtain from system properties private int proxyPort; private String proxyHost = null; private String proxyUserName = null; private String proxyPasswd = null; private HttpClientHelper httpClientHelper; private static HttpClient httpClient; public HttpClientHandler() { configureProxy(); } private void configureProxy() { proxyHost = System.getProperty("http.proxyHost"); // TODO constant is better ... if (useProxy()) { proxyPort = Integer.parseInt(System.getProperty("http.proxyPort", "80")); proxyUserName = System.getProperty("http.proxyUser"); proxyPasswd = System.getProperty("http.proxyPassword"); // It seems there is no equivalent in HttpClient for // 'http.nonProxyHosts' property Message.verbose( "proxy configured: host=" + proxyHost + " port=" + proxyPort + " user=" + proxyUserName); } else { Message.verbose("no proxy configured"); } } public InputStream openStream(URL url) throws IOException { GetMethod get = doGet(url, 0); if (!checkStatusCode(url, get)) { get.releaseConnection(); throw new IOException("The HTTP response code for " + url + " did not indicate a success." + " See log for more detail."); } Header encoding = get.getResponseHeader("Content-Encoding"); return getDecodingInputStream(encoding == null ? null : encoding.getValue(), get.getResponseBodyAsStream()); } public void download(URL src, File dest, CopyProgressListener l) throws IOException { GetMethod get = doGet(src, 0); try { // We can only figure the content we got is want we want if the status is success. if (!checkStatusCode(src, get)) { throw new IOException("The HTTP response code for " + src + " did not indicate a success." + " See log for more detail."); } Header encoding = get.getResponseHeader("Content-Encoding"); InputStream is = getDecodingInputStream(encoding == null ? null : encoding.getValue(), get.getResponseBodyAsStream()); FileUtil.copy(is, dest, l); dest.setLastModified(getLastModified(get)); } finally { get.releaseConnection(); } } public void upload(File src, URL dest, CopyProgressListener l) throws IOException { HttpClient client = getClient(); PutMethod put = new PutMethod(normalizeToString(dest)); put.setDoAuthentication(useAuthentication(dest) || useProxyAuthentication()); put.getParams().setBooleanParameter("http.protocol.expect-continue", true); try { put.setRequestEntity(new FileRequestEntity(src)); int statusCode = client.executeMethod(put); validatePutStatusCode(dest, statusCode, null); } finally { put.releaseConnection(); } } public URLInfo getURLInfo(URL url) { return getURLInfo(url, 0); } public URLInfo getURLInfo(URL url, int timeout) { HttpMethodBase method = null; try { if (getRequestMethod() == URLHandler.REQUEST_METHOD_HEAD) { method = doHead(url, timeout); } else { method = doGet(url, timeout); } if (checkStatusCode(url, method)) { return new URLInfo(true, getResponseContentLength(method), getLastModified(method), method.getRequestCharSet()); } } catch (HttpException e) { Message.error("HttpClientHandler: " + e.getMessage() + ":" + e.getReasonCode() + "=" + e.getReason() + " url=" + url); } catch (UnknownHostException e) { Message.warn("Host " + e.getMessage() + " not found. url=" + url); Message.info("You probably access the destination server through " + "a proxy server that is not well configured."); } catch (IOException e) { Message.error("HttpClientHandler: " + e.getMessage() + " url=" + url); } catch (IllegalArgumentException e) { // thrown by HttpClient to indicate the URL is not valid, this happens for instance // when trying to download a dynamic version (cfr IVY-390) } finally { if (method != null) { method.releaseConnection(); } } return UNAVAILABLE; } private boolean checkStatusCode(URL url, HttpMethodBase method) throws IOException { int status = method.getStatusCode(); if (status == HttpStatus.SC_OK) { return true; } // IVY-1328: some servers return a 204 on a HEAD request if ("HEAD".equals(method.getName()) && (status == 204)) { return true; } Message.debug("HTTP response status: " + status + " url=" + url); if (status == HttpStatus.SC_PROXY_AUTHENTICATION_REQUIRED) { Message.warn("Your proxy requires authentication."); } else if (String.valueOf(status).startsWith("4")) { Message.verbose("CLIENT ERROR: " + method.getStatusText() + " url=" + url); } else if (String.valueOf(status).startsWith("5")) { Message.error("SERVER ERROR: " + method.getStatusText() + " url=" + url); } return false; } private long getLastModified(HttpMethodBase method) { Header header = method.getResponseHeader("last-modified"); if (header != null) { String lastModified = header.getValue(); try { return LAST_MODIFIED_FORMAT.parse(lastModified).getTime(); } catch (ParseException e) { // ignored } return System.currentTimeMillis(); } else { return System.currentTimeMillis(); } } private long getResponseContentLength(HttpMethodBase head) { return getHttpClientHelper().getResponseContentLength(head); } private HttpClientHelper getHttpClientHelper() { if (httpClientHelper == null) { // use commons httpclient 3.0 if available try { HttpMethodBase.class.getMethod("getResponseContentLength", new Class[0]); httpClientHelper = new HttpClientHelper3x(); Message.verbose("using commons httpclient 3.x helper"); } catch (SecurityException e) { Message.verbose("unable to get access to getResponseContentLength of " + "commons-httpclient HeadMethod. Please use commons-httpclient 3.0 or " + "use ivy with sufficient security permissions."); Message.verbose("exception: " + e.getMessage()); httpClientHelper = new HttpClientHelper2x(); Message.verbose("using commons httpclient 2.x helper"); } catch (NoSuchMethodException e) { httpClientHelper = new HttpClientHelper2x(); Message.verbose("using commons httpclient 2.x helper"); } } return httpClientHelper; } public int getHttpClientMajorVersion() { HttpClientHelper helper = getHttpClientHelper(); return helper.getHttpClientMajorVersion(); } private GetMethod doGet(URL url, int timeout) throws IOException { HttpClient client = getClient(); client.setTimeout(timeout); GetMethod get = new GetMethod(normalizeToString(url)); get.setDoAuthentication(useAuthentication(url) || useProxyAuthentication()); get.setRequestHeader("Accept-Encoding", "gzip,deflate"); client.executeMethod(get); return get; } private HeadMethod doHead(URL url, int timeout) throws IOException { HttpClient client = getClient(); client.setTimeout(timeout); HeadMethod head = new HeadMethod(normalizeToString(url)); head.setDoAuthentication(useAuthentication(url) || useProxyAuthentication()); client.executeMethod(head); return head; } private HttpClient getClient() { if (httpClient == null) { final MultiThreadedHttpConnectionManager connManager = new MultiThreadedHttpConnectionManager(); httpClient = new HttpClient(connManager); Runtime.getRuntime().addShutdownHook(new Thread(new Runnable() { public void run() { connManager.shutdown(); } })); List authPrefs = new ArrayList(3); authPrefs.add(AuthPolicy.DIGEST); authPrefs.add(AuthPolicy.BASIC); authPrefs.add(AuthPolicy.NTLM); // put it at the end to give less priority (IVY-213) httpClient.getParams().setParameter(AuthPolicy.AUTH_SCHEME_PRIORITY, authPrefs); if (useProxy()) { httpClient.getHostConfiguration().setProxy(proxyHost, proxyPort); if (useProxyAuthentication()) { httpClient.getState().setProxyCredentials( new AuthScope(proxyHost, proxyPort, AuthScope.ANY_REALM), createCredentials(proxyUserName, proxyPasswd)); } } // user-agent httpClient.getParams().setParameter(HttpMethodParams.USER_AGENT, getUserAgent()); // authentication httpClient.getParams().setParameter(CredentialsProvider.PROVIDER, new IvyCredentialsProvider()); } return httpClient; } private boolean useProxy() { return proxyHost != null && proxyHost.trim().length() > 0; } private boolean useAuthentication(URL url) { return CredentialsStore.INSTANCE.hasCredentials(url.getHost()); } private boolean useProxyAuthentication() { return (proxyUserName != null && proxyUserName.trim().length() > 0); } private static final class HttpClientHelper3x implements HttpClientHelper { private static final int VERSION = 3; private HttpClientHelper3x() { } public long getResponseContentLength(HttpMethodBase method) { return method.getResponseContentLength(); } /** * {@inheritDoc} */ public int getHttpClientMajorVersion() { return VERSION; } } private static final class HttpClientHelper2x implements HttpClientHelper { private static final int VERSION = 2; private HttpClientHelper2x() { } public long getResponseContentLength(HttpMethodBase method) { Header header = method.getResponseHeader("Content-Length"); if (header != null) { try { return Integer.parseInt(header.getValue()); } catch (NumberFormatException e) { Message.verbose("Invalid content-length value: " + e.getMessage()); } } return 0; } /** * {@inheritDoc} */ public int getHttpClientMajorVersion() { return VERSION; } } public interface HttpClientHelper { long getResponseContentLength(HttpMethodBase method); int getHttpClientMajorVersion(); } private static class IvyCredentialsProvider implements CredentialsProvider { public Credentials getCredentials(AuthScheme scheme, String host, int port, boolean proxy) throws CredentialsNotAvailableException { String realm = scheme.getRealm(); org.apache.ivy.util.Credentials c = CredentialsStore.INSTANCE.getCredentials(realm, host); if (c != null) { return createCredentials(c.getUserName(), c.getPasswd()); } return null; } } private static Credentials createCredentials(String username, String password) { String user; String domain; int backslashIndex = username.indexOf('\\'); if (backslashIndex >= 0) { user = username.substring(backslashIndex + 1); domain = username.substring(0, backslashIndex); } else { user = username; domain = System.getProperty("http.auth.ntlm.domain", ""); } return new NTCredentials(user, password, HostUtil.getLocalHostName(), domain); } private static class FileRequestEntity implements RequestEntity { private File file; public FileRequestEntity(File file) { this.file = file; } public long getContentLength() { return file.length(); } public String getContentType() { return null; } public boolean isRepeatable() { return true; } public void writeRequest(OutputStream out) throws IOException { InputStream instream = new FileInputStream(file); try { FileUtil.copy(instream, out, null, false); } finally { instream.close(); } } } }