Java tutorial
package com.apache.ivy; /* * 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. * */ import java.io.BufferedWriter; import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.io.UnsupportedEncodingException; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.net.URLEncoder; import java.net.UnknownHostException; import java.nio.charset.Charset; import java.util.ArrayList; import java.util.List; import org.apache.http.NameValuePair; import com.apache.ivy.ApacheURLLister; import com.apache.ivy.CopyProgressListener; import com.apache.ivy.FileUtil; /** * */ public class BasicURLHandler extends AbstractURLHandler { private static final int BUFFER_SIZE = 64 * 1024; private static final class HttpStatus { static final int SC_OK = 200; static final int SC_PROXY_AUTHENTICATION_REQUIRED = 407; private HttpStatus() { } } public URLInfo getURLInfo(URL url) { return getURLInfo(url, 0); } public URLInfo getURLInfo(URL url, int timeout) { // Install the IvyAuthenticator if ("http".equals(url.getProtocol()) || "https".equals(url.getProtocol())) { IvyAuthenticator.install(); } URLConnection con = null; try { url = normalizeToURL(url); con = url.openConnection(); con.setRequestProperty("User-Agent", "Apache Ivy/1.0");//+ Ivy.getIvyVersion()); if (con instanceof HttpURLConnection) { HttpURLConnection httpCon = (HttpURLConnection) con; if (getRequestMethod() == URLHandler.REQUEST_METHOD_HEAD) { httpCon.setRequestMethod("HEAD"); } if (checkStatusCode(url, httpCon)) { String bodyCharset = getCharSetFromContentType(con.getContentType()); return new URLInfo(true, httpCon.getContentLength(), con.getLastModified(), bodyCharset); } } else { int contentLength = con.getContentLength(); if (contentLength <= 0) { return UNAVAILABLE; } else { // TODO: not HTTP... maybe we *don't* want to default to ISO-8559-1 here? String bodyCharset = getCharSetFromContentType(con.getContentType()); return new URLInfo(true, contentLength, con.getLastModified(), bodyCharset); } } } 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("Server access error at url " + url, e); } finally { disconnect(con); } return UNAVAILABLE; } /** * Extract the charset from the Content-Type header string, or default to ISO-8859-1 as per * rfc2616-sec3.html#sec3.7.1 . * * @param contentType * the Content-Type header string * @return the charset as specified in the content type, or ISO-8859-1 if unspecified. */ public static String getCharSetFromContentType(String contentType) { String charSet = null; if (contentType != null) { String[] elements = contentType.split(";"); for (int i = 0; i < elements.length; i++) { String element = elements[i].trim(); if (element.toLowerCase().startsWith("charset=")) { charSet = element.substring("charset=".length()); } } } if (charSet == null || charSet.length() == 0) { // default to ISO-8859-1 as per rfc2616-sec3.html#sec3.7.1 charSet = "ISO-8859-1"; } return charSet; } private boolean checkStatusCode(URL url, HttpURLConnection con) throws IOException { int status = con.getResponseCode(); if (status == HttpStatus.SC_OK) { return true; } // IVY-1328: some servers return a 204 on a HEAD request if ("HEAD".equals(con.getRequestMethod()) && (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: " + con.getResponseMessage() + " url=" + url); } else if (String.valueOf(status).startsWith("5")) { //Message.error("SERVER ERROR: " + con.getResponseMessage() + " url=" + url); } return false; } private String getQuery(List<NameValuePair> params) throws UnsupportedEncodingException { StringBuilder result = new StringBuilder(); boolean first = true; for (NameValuePair pair : params) { if (first) first = false; else result.append("&"); result.append(URLEncoder.encode(pair.getName(), "UTF-8")); result.append("="); result.append(URLEncoder.encode(pair.getValue(), "UTF-8")); } return result.toString(); } public InputStream openStreamPost(URL url, ArrayList<NameValuePair> postData) throws IOException { // Install the IvyAuthenticator if ("http".equals(url.getProtocol()) || "https".equals(url.getProtocol())) { IvyAuthenticator.install(); } URLConnection conn = null; try { url = normalizeToURL(url); conn = url.openConnection(); conn.setRequestProperty("User-Agent", "Apache Ivy/1.0");// + Ivy.getIvyVersion()); conn.setRequestProperty("Accept-Encoding", "gzip,deflate"); if (conn instanceof HttpURLConnection) { HttpURLConnection httpCon = (HttpURLConnection) conn; httpCon.setRequestMethod("POST"); httpCon.setDoInput(true); httpCon.setDoOutput(true); byte[] postDataBytes = getQuery(postData).getBytes(Charset.forName("UTF-8")); String contentLength = String.valueOf(postDataBytes.length); httpCon.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); httpCon.setRequestProperty("Content-Length", contentLength); httpCon.setDoOutput(true); httpCon.connect(); httpCon.getOutputStream().write(postDataBytes); conn.getOutputStream().flush(); if (!checkStatusCode(url, httpCon)) { throw new IOException("The HTTP response code for " + url + " did not indicate a success." + " See log for more detail."); } } // read the output InputStream inStream = getDecodingInputStream(conn.getContentEncoding(), conn.getInputStream()); ByteArrayOutputStream outStream = new ByteArrayOutputStream(); byte[] buffer = new byte[BUFFER_SIZE]; int len; while ((len = inStream.read(buffer)) > 0) { outStream.write(buffer, 0, len); } return new ByteArrayInputStream(outStream.toByteArray()); } finally { disconnect(conn); } } public InputStream openStream(URL url) throws IOException { // Install the IvyAuthenticator if ("http".equals(url.getProtocol()) || "https".equals(url.getProtocol())) { IvyAuthenticator.install(); } URLConnection conn = null; try { url = normalizeToURL(url); conn = url.openConnection(); conn.setRequestProperty("User-Agent", "Apache Ivy/1.0");// + Ivy.getIvyVersion()); conn.setRequestProperty("Accept-Encoding", "gzip,deflate"); if (conn instanceof HttpURLConnection) { HttpURLConnection httpCon = (HttpURLConnection) conn; if (!checkStatusCode(url, httpCon)) { throw new IOException("The HTTP response code for " + url + " did not indicate a success." + " See log for more detail."); } } InputStream inStream = getDecodingInputStream(conn.getContentEncoding(), conn.getInputStream()); ByteArrayOutputStream outStream = new ByteArrayOutputStream(); byte[] buffer = new byte[BUFFER_SIZE]; int len; while ((len = inStream.read(buffer)) > 0) { outStream.write(buffer, 0, len); } return new ByteArrayInputStream(outStream.toByteArray()); } finally { disconnect(conn); } } public void download(URL src, File dest, CopyProgressListener l) throws IOException { // Install the IvyAuthenticator if ("http".equals(src.getProtocol()) || "https".equals(src.getProtocol())) { IvyAuthenticator.install(); } URLConnection srcConn = null; try { src = normalizeToURL(src); srcConn = src.openConnection(); srcConn.setRequestProperty("User-Agent", "Apache Ivy/1.0");// + Ivy.getIvyVersion()); srcConn.setRequestProperty("Accept-Encoding", "gzip,deflate"); if (srcConn instanceof HttpURLConnection) { HttpURLConnection httpCon = (HttpURLConnection) srcConn; if (!checkStatusCode(src, httpCon)) { throw new IOException("The HTTP response code for " + src + " did not indicate a success." + " See log for more detail."); } } // do the download InputStream inStream = getDecodingInputStream(srcConn.getContentEncoding(), srcConn.getInputStream()); FileUtil.copy(inStream, dest, l); // check content length only if content was not encoded if (srcConn.getContentEncoding() == null) { int contentLength = srcConn.getContentLength(); if (contentLength != -1 && dest.length() != contentLength) { dest.delete(); throw new IOException("Downloaded file size doesn't match expected Content Length for " + src + ". Please retry."); } } // update modification date long lastModified = srcConn.getLastModified(); if (lastModified > 0) { dest.setLastModified(lastModified); } } finally { disconnect(srcConn); } } public void upload(File source, URL dest, CopyProgressListener l) throws IOException { if (!"http".equals(dest.getProtocol()) && !"https".equals(dest.getProtocol())) { throw new UnsupportedOperationException("URL repository only support HTTP PUT at the moment"); } // Install the IvyAuthenticator IvyAuthenticator.install(); HttpURLConnection conn = null; try { dest = normalizeToURL(dest); conn = (HttpURLConnection) dest.openConnection(); conn.setDoOutput(true); conn.setRequestMethod("PUT"); conn.setRequestProperty("User-Agent", "Apache Ivy/1.0");// + Ivy.getIvyVersion()); conn.setRequestProperty("Content-type", "application/octet-stream"); conn.setRequestProperty("Content-length", Long.toString(source.length())); conn.setInstanceFollowRedirects(true); InputStream in = new FileInputStream(source); try { OutputStream os = conn.getOutputStream(); FileUtil.copy(in, os, l); } finally { try { in.close(); } catch (IOException e) { /* ignored */ } } validatePutStatusCode(dest, conn.getResponseCode(), conn.getResponseMessage()); } finally { disconnect(conn); } } private void disconnect(URLConnection con) { if (con instanceof HttpURLConnection) { if (!"HEAD".equals(((HttpURLConnection) con).getRequestMethod())) { // We must read the response body before disconnecting! // Cfr. http://java.sun.com/j2se/1.5.0/docs/guide/net/http-keepalive.html // [quote]Do not abandon a connection by ignoring the response body. Doing // so may results in idle TCP connections.[/quote] readResponseBody((HttpURLConnection) con); } ((HttpURLConnection) con).disconnect(); } else if (con != null) { try { con.getInputStream().close(); } catch (IOException e) { // ignored } } } /** * Read and ignore the response body. */ private void readResponseBody(HttpURLConnection conn) { byte[] buffer = new byte[BUFFER_SIZE]; InputStream inStream = null; try { inStream = conn.getInputStream(); while (inStream.read(buffer) > 0) { //Skip content } } catch (IOException e) { // ignore } finally { if (inStream != null) { try { inStream.close(); } catch (IOException e) { // ignore } } } InputStream errStream = conn.getErrorStream(); if (errStream != null) { try { while (errStream.read(buffer) > 0) { //Skip content } } catch (IOException e) { // ignore } finally { try { errStream.close(); } catch (IOException e) { // ignore } } } } }