Java tutorial
/* * Copyright (C) 2010, Google Inc. * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org> * and other copyright owners as documented in the project's IP log. * * This program and the accompanying materials are made available * under the terms of the Eclipse Distribution License v1.0 which * accompanies this distribution, is reproduced below, and is * available at http://www.eclipse.org/org/documents/edl-v10.php * * All rights reserved. * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * - Neither the name of the Eclipse Foundation, Inc. nor the * names of its contributors may be used to endorse or promote * products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package org.eclipse.jgit.util; import static java.nio.charset.StandardCharsets.UTF_8; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.net.ConnectException; import java.net.Proxy; import java.net.ProxySelector; import java.net.URI; import java.net.URISyntaxException; import java.net.URL; import java.net.URLEncoder; import java.security.KeyManagementException; import java.security.NoSuchAlgorithmException; import java.security.cert.X509Certificate; import java.text.MessageFormat; import javax.net.ssl.HostnameVerifier; import javax.net.ssl.SSLSession; import javax.net.ssl.TrustManager; import javax.net.ssl.X509TrustManager; import org.eclipse.jgit.internal.JGitText; import org.eclipse.jgit.transport.http.HttpConnection; /** * Extra utilities to support usage of HTTP. */ public class HttpSupport { /** The {@code GET} HTTP method. */ public static final String METHOD_GET = "GET"; //$NON-NLS-1$ /** The {@code HEAD} HTTP method. * @since 4.3 */ public static final String METHOD_HEAD = "HEAD"; //$NON-NLS-1$ /** The {@code POST} HTTP method. * @since 4.3 */ public static final String METHOD_PUT = "PUT"; //$NON-NLS-1$ /** The {@code POST} HTTP method. */ public static final String METHOD_POST = "POST"; //$NON-NLS-1$ /** The {@code Cache-Control} header. */ public static final String HDR_CACHE_CONTROL = "Cache-Control"; //$NON-NLS-1$ /** The {@code Pragma} header. */ public static final String HDR_PRAGMA = "Pragma"; //$NON-NLS-1$ /** The {@code User-Agent} header. */ public static final String HDR_USER_AGENT = "User-Agent"; //$NON-NLS-1$ /** * The {@code Server} header. * @since 4.0 */ public static final String HDR_SERVER = "Server"; //$NON-NLS-1$ /** The {@code Date} header. */ public static final String HDR_DATE = "Date"; //$NON-NLS-1$ /** The {@code Expires} header. */ public static final String HDR_EXPIRES = "Expires"; //$NON-NLS-1$ /** The {@code ETag} header. */ public static final String HDR_ETAG = "ETag"; //$NON-NLS-1$ /** The {@code If-None-Match} header. */ public static final String HDR_IF_NONE_MATCH = "If-None-Match"; //$NON-NLS-1$ /** The {@code Last-Modified} header. */ public static final String HDR_LAST_MODIFIED = "Last-Modified"; //$NON-NLS-1$ /** The {@code If-Modified-Since} header. */ public static final String HDR_IF_MODIFIED_SINCE = "If-Modified-Since"; //$NON-NLS-1$ /** The {@code Accept} header. */ public static final String HDR_ACCEPT = "Accept"; //$NON-NLS-1$ /** The {@code Content-Type} header. */ public static final String HDR_CONTENT_TYPE = "Content-Type"; //$NON-NLS-1$ /** The {@code Content-Length} header. */ public static final String HDR_CONTENT_LENGTH = "Content-Length"; //$NON-NLS-1$ /** The {@code Content-Encoding} header. */ public static final String HDR_CONTENT_ENCODING = "Content-Encoding"; //$NON-NLS-1$ /** The {@code Content-Range} header. */ public static final String HDR_CONTENT_RANGE = "Content-Range"; //$NON-NLS-1$ /** The {@code Accept-Ranges} header. */ public static final String HDR_ACCEPT_RANGES = "Accept-Ranges"; //$NON-NLS-1$ /** The {@code If-Range} header. */ public static final String HDR_IF_RANGE = "If-Range"; //$NON-NLS-1$ /** The {@code Range} header. */ public static final String HDR_RANGE = "Range"; //$NON-NLS-1$ /** The {@code Accept-Encoding} header. */ public static final String HDR_ACCEPT_ENCODING = "Accept-Encoding"; //$NON-NLS-1$ /** * The {@code Location} header. * @since 4.7 */ public static final String HDR_LOCATION = "Location"; //$NON-NLS-1$ /** The {@code gzip} encoding value for {@link #HDR_ACCEPT_ENCODING}. */ public static final String ENCODING_GZIP = "gzip"; //$NON-NLS-1$ /** * The {@code x-gzip} encoding value for {@link #HDR_ACCEPT_ENCODING}. * @since 4.6 */ public static final String ENCODING_X_GZIP = "x-gzip"; //$NON-NLS-1$ /** The standard {@code text/plain} MIME type. */ public static final String TEXT_PLAIN = "text/plain"; //$NON-NLS-1$ /** The {@code Authorization} header. */ public static final String HDR_AUTHORIZATION = "Authorization"; //$NON-NLS-1$ /** The {@code WWW-Authenticate} header. */ public static final String HDR_WWW_AUTHENTICATE = "WWW-Authenticate"; //$NON-NLS-1$ /** * The {@code Cookie} header. * * @since 5.4 */ public static final String HDR_COOKIE = "Cookie"; //$NON-NLS-1$ /** * The {@code Set-Cookie} header. * * @since 5.4 */ public static final String HDR_SET_COOKIE = "Set-Cookie"; //$NON-NLS-1$ /** * The {@code Set-Cookie2} header. * * @since 5.4 */ public static final String HDR_SET_COOKIE2 = "Set-Cookie2"; //$NON-NLS-1$ /** * URL encode a value string into an output buffer. * * @param urlstr * the output buffer. * @param key * value which must be encoded to protected special characters. */ public static void encode(StringBuilder urlstr, String key) { if (key == null || key.length() == 0) return; try { urlstr.append(URLEncoder.encode(key, UTF_8.name())); } catch (UnsupportedEncodingException e) { throw new RuntimeException(JGitText.get().couldNotURLEncodeToUTF8, e); } } /** * Get the HTTP response code from the request. * <p> * Roughly the same as <code>c.getResponseCode()</code> but the * ConnectException is translated to be more understandable. * * @param c * connection the code should be obtained from. * @return r HTTP status code, usually 200 to indicate success. See * {@link org.eclipse.jgit.transport.http.HttpConnection} for other * defined constants. * @throws java.io.IOException * communications error prevented obtaining the response code. * @since 3.3 */ public static int response(HttpConnection c) throws IOException { try { return c.getResponseCode(); } catch (ConnectException ce) { final URL url = c.getURL(); final String host = (url == null) ? "<null>" : url.getHost(); //$NON-NLS-1$ // The standard J2SE error message is not very useful. // if ("Connection timed out: connect".equals(ce.getMessage())) //$NON-NLS-1$ throw new ConnectException(MessageFormat.format(JGitText.get().connectionTimeOut, host)); throw new ConnectException(ce.getMessage() + " " + host); //$NON-NLS-1$ } } /** * Get the HTTP response code from the request. * <p> * Roughly the same as <code>c.getResponseCode()</code> but the * ConnectException is translated to be more understandable. * * @param c * connection the code should be obtained from. * @return r HTTP status code, usually 200 to indicate success. See * {@link org.eclipse.jgit.transport.http.HttpConnection} for other * defined constants. * @throws java.io.IOException * communications error prevented obtaining the response code. */ public static int response(java.net.HttpURLConnection c) throws IOException { try { return c.getResponseCode(); } catch (ConnectException ce) { final URL url = c.getURL(); final String host = (url == null) ? "<null>" : url.getHost(); //$NON-NLS-1$ // The standard J2SE error message is not very useful. // if ("Connection timed out: connect".equals(ce.getMessage())) //$NON-NLS-1$ throw new ConnectException(MessageFormat.format(JGitText.get().connectionTimeOut, host)); throw new ConnectException(ce.getMessage() + " " + host); //$NON-NLS-1$ } } /** * Extract a HTTP header from the response. * * @param c * connection the header should be obtained from. * @param headerName * the header name * @return the header value * @throws java.io.IOException * communications error prevented obtaining the header. * @since 4.7 */ public static String responseHeader(final HttpConnection c, final String headerName) throws IOException { return c.getHeaderField(headerName); } /** * Determine the proxy server (if any) needed to obtain a URL. * * @param proxySelector * proxy support for the caller. * @param u * location of the server caller wants to talk to. * @return proxy to communicate with the supplied URL. * @throws java.net.ConnectException * the proxy could not be computed as the supplied URL could not * be read. This failure should never occur. */ public static Proxy proxyFor(ProxySelector proxySelector, URL u) throws ConnectException { try { URI uri = new URI(u.getProtocol(), null, u.getHost(), u.getPort(), null, null, null); return proxySelector.select(uri).get(0); } catch (URISyntaxException e) { final ConnectException err; err = new ConnectException(MessageFormat.format(JGitText.get().cannotDetermineProxyFor, u)); err.initCause(e); throw err; } } /** * Disable SSL and hostname verification for given HTTP connection * * @param conn * a {@link org.eclipse.jgit.transport.http.HttpConnection} * object. * @throws java.io.IOException * @since 4.3 */ public static void disableSslVerify(HttpConnection conn) throws IOException { final TrustManager[] trustAllCerts = new TrustManager[] { new DummyX509TrustManager() }; try { conn.configure(null, trustAllCerts, null); conn.setHostnameVerifier(new DummyHostnameVerifier()); } catch (KeyManagementException | NoSuchAlgorithmException e) { throw new IOException(e.getMessage()); } } private static class DummyX509TrustManager implements X509TrustManager { @Override public X509Certificate[] getAcceptedIssuers() { return null; } @Override public void checkClientTrusted(X509Certificate[] certs, String authType) { // no check } @Override public void checkServerTrusted(X509Certificate[] certs, String authType) { // no check } } private static class DummyHostnameVerifier implements HostnameVerifier { @Override public boolean verify(String hostname, SSLSession session) { // always accept return true; } } private HttpSupport() { // Utility class only. } }