Java example source code file (HttpStreams.java)

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Java - Java tags/keywords

abstracthandler, chunkederrorhandler, errorhandler, exception, fixedhandler, hello, httpserver, httpurlconnection, inputstream, ioexception, net, network, outputstream, responsecache, string, trivialcachehandler, util

The HttpStreams.java Java example source code

/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/**
 * @test
 * @bug 8011719
 * @summary Basic checks to verify behavior of returned input streams
 */

import com.sun.net.httpserver.HttpExchange;
import com.sun.net.httpserver.HttpHandler;
import com.sun.net.httpserver.HttpServer;
import java.io.*;
import java.net.*;
import java.nio.charset.StandardCharsets;
import java.util.*;

public class HttpStreams {

    void client(String u) throws Exception {
        byte[] ba = new byte[5];
        HttpURLConnection urlc = (HttpURLConnection)(new URL(u)).openConnection();
        int resp = urlc.getResponseCode();
        InputStream is;
        if (resp == 200)
            is = urlc.getInputStream();
        else
            is = urlc.getErrorStream();

        expectNoThrow(() -> { is.read(); }, "read on open stream should not throw :" + u);
        expectNoThrow(() -> { is.close(); }, "close should never throw: " + u);
        expectNoThrow(() -> { is.close(); }, "close should never throw: " + u);
        expectThrow(() -> { is.read(); }, "read on closed stream should throw: " + u);
        expectThrow(() -> { is.read(ba); }, "read on closed stream should throw: " + u);
        expectThrow(() -> { is.read(ba, 0, 2); }, "read on closed stream should throw: " + u);
    }

    void test() throws Exception {
        HttpServer server = null;
        try {
            server = startHttpServer();
            String baseUrl = "http://localhost:" + server.getAddress().getPort() + "/";
            client(baseUrl +  "chunked/");
            client(baseUrl +  "fixed/");
            client(baseUrl +  "error/");
            client(baseUrl +  "chunkedError/");

            // Test with a response cache
            ResponseCache ch = ResponseCache.getDefault();
            ResponseCache.setDefault(new TrivialCacheHandler());
            try {
                client(baseUrl +  "chunked/");
                client(baseUrl +  "fixed/");
                client(baseUrl +  "error/");
                client(baseUrl +  "chunkedError/");
            } finally {
                ResponseCache.setDefault(ch);
            }
        } finally {
            if (server != null)
                server.stop(0);
        }

        System.out.println("passed: " + pass + ", failed: " + fail);
        if (fail > 0)
            throw new RuntimeException("some tests failed check output");
    }

    public static void main(String[] args) throws Exception {
        (new HttpStreams()).test();
    }

    // HTTP Server
    HttpServer startHttpServer() throws IOException {
        HttpServer httpServer = HttpServer.create(new InetSocketAddress(0), 0);
        httpServer.createContext("/chunked/", new ChunkedHandler());
        httpServer.createContext("/fixed/", new FixedHandler());
        httpServer.createContext("/error/", new ErrorHandler());
        httpServer.createContext("/chunkedError/", new ChunkedErrorHandler());
        httpServer.start();
        return httpServer;
    }

    static abstract class AbstractHandler implements HttpHandler {
        @Override
        public void handle(HttpExchange t) throws IOException {
            try (InputStream is = t.getRequestBody()) {
                while (is.read() != -1);
            }
            t.sendResponseHeaders(respCode(), length());
            try (OutputStream os = t.getResponseBody()) {
                os.write(message());
            }
            t.close();
        }

        abstract int respCode();
        abstract int length();
        abstract byte[] message();
    }

    static class ChunkedHandler extends AbstractHandler {
        static final byte[] ba =
                "Hello there from chunked handler!".getBytes(StandardCharsets.US_ASCII);
        int respCode() { return 200; }
        int length() { return 0; }
        byte[] message() { return ba; }
    }

    static class FixedHandler extends AbstractHandler {
        static final byte[] ba =
                "Hello there from fixed handler!".getBytes(StandardCharsets.US_ASCII);
        int respCode() { return 200; }
        int length() { return ba.length; }
        byte[] message() { return ba; }
    }

    static class ErrorHandler extends AbstractHandler {
        static final byte[] ba =
                "This is an error mesg from the server!".getBytes(StandardCharsets.US_ASCII);
        int respCode() { return 400; }
        int length() { return ba.length; }
        byte[] message() { return ba; }
    }

    static class ChunkedErrorHandler extends ErrorHandler {
        int length() { return 0; }
    }

    static class TrivialCacheHandler extends ResponseCache
    {
       public CacheResponse get(URI uri, String rqstMethod, Map rqstHeaders) {
          return null;
       }

       public CacheRequest put(URI uri, URLConnection conn) {
          return new TrivialCacheRequest();
       }
    }

    static class TrivialCacheRequest extends CacheRequest
    {
       ByteArrayOutputStream baos = new ByteArrayOutputStream();
       public void abort() {}
       public OutputStream getBody() throws IOException { return baos; }
    }

    static interface ThrowableRunnable {
        void run() throws IOException;
    }

    void expectThrow(ThrowableRunnable r, String msg) {
        try { r.run(); fail(msg); } catch (IOException x) { pass(); }
    }

    void expectNoThrow(ThrowableRunnable r, String msg) {
        try { r.run(); pass(); } catch (IOException x) { fail(msg, x); }
    }

    private int pass;
    private int fail;
    void pass() { pass++; }
    void fail(String msg, Exception x) { System.out.println(msg); x.printStackTrace(); fail++; }
    void fail(String msg) { System.out.println(msg); Thread.dumpStack(); fail++; }
}