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. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package org.apache.http.impl.nio; import java.io.IOException; import java.net.InetAddress; import java.net.InetSocketAddress; import java.net.SocketAddress; import java.nio.channels.ReadableByteChannel; import java.nio.channels.WritableByteChannel; import org.apache.http.ConnectionClosedException; import org.apache.http.Header; import org.apache.http.HttpConnectionMetrics; import org.apache.http.HttpEntity; import org.apache.http.HttpException; import org.apache.http.HttpInetConnection; import org.apache.http.HttpMessage; import org.apache.http.HttpRequest; import org.apache.http.HttpResponse; import org.apache.http.entity.BasicHttpEntity; import org.apache.http.entity.ContentLengthStrategy; import org.apache.http.impl.HttpConnectionMetricsImpl; import org.apache.http.impl.entity.LaxContentLengthStrategy; import org.apache.http.impl.entity.StrictContentLengthStrategy; import org.apache.http.impl.io.HttpTransportMetricsImpl; import org.apache.http.nio.ContentDecoder; import org.apache.http.nio.ContentEncoder; import org.apache.http.nio.NHttpConnection; import org.apache.http.impl.nio.codecs.ChunkDecoder; import org.apache.http.impl.nio.codecs.ChunkEncoder; import org.apache.http.impl.nio.codecs.IdentityDecoder; import org.apache.http.impl.nio.codecs.IdentityEncoder; import org.apache.http.impl.nio.codecs.LengthDelimitedDecoder; import org.apache.http.impl.nio.codecs.LengthDelimitedEncoder; import org.apache.http.impl.nio.reactor.SessionInputBufferImpl; import org.apache.http.impl.nio.reactor.SessionOutputBufferImpl; import org.apache.http.io.HttpTransportMetrics; import org.apache.http.nio.reactor.EventMask; import org.apache.http.nio.reactor.IOSession; import org.apache.http.nio.reactor.SessionBufferStatus; import org.apache.http.nio.reactor.SessionInputBuffer; import org.apache.http.nio.reactor.SessionOutputBuffer; import org.apache.http.nio.util.ByteBufferAllocator; import org.apache.http.params.HttpConnectionParams; import org.apache.http.params.HttpParams; import org.apache.http.protocol.HTTP; import org.apache.http.protocol.HttpContext; /** * This class serves as a base for all {@link NHttpConnection} implementations * and implements functionality common to both client and server * HTTP connections. * <p> * The following parameters can be used to customize the behavior of this * class: * <ul> * <li>{@link org.apache.http.params.CoreProtocolPNames#HTTP_ELEMENT_CHARSET}</li> * <li>{@link org.apache.http.params.CoreConnectionPNames#SOCKET_BUFFER_SIZE}</li> * </ul> * * @since 4.0 */ public class NHttpConnectionBase implements NHttpConnection, HttpInetConnection, SessionBufferStatus { protected final ContentLengthStrategy incomingContentStrategy; protected final ContentLengthStrategy outgoingContentStrategy; protected final SessionInputBufferImpl inbuf; protected final SessionOutputBufferImpl outbuf; protected final HttpTransportMetricsImpl inTransportMetrics; protected final HttpTransportMetricsImpl outTransportMetrics; protected final HttpConnectionMetricsImpl connMetrics; protected HttpContext context; protected IOSession session; protected SocketAddress remote; protected volatile ContentDecoder contentDecoder; protected volatile boolean hasBufferedInput; protected volatile ContentEncoder contentEncoder; protected volatile boolean hasBufferedOutput; protected volatile HttpRequest request; protected volatile HttpResponse response; protected volatile int status; /** * Creates a new instance of this class given the underlying I/O session. * * @param session the underlying I/O session. * @param allocator byte buffer allocator. * @param params HTTP parameters. */ public NHttpConnectionBase(final IOSession session, final ByteBufferAllocator allocator, final HttpParams params) { super(); if (session == null) { throw new IllegalArgumentException("I/O session may not be null"); } if (params == null) { throw new IllegalArgumentException("HTTP params may not be null"); } int buffersize = HttpConnectionParams.getSocketBufferSize(params); int linebuffersize = buffersize; if (linebuffersize > 512) { linebuffersize = 512; } this.inbuf = new SessionInputBufferImpl(buffersize, linebuffersize, allocator, params); this.outbuf = new SessionOutputBufferImpl(buffersize, linebuffersize, allocator, params); this.incomingContentStrategy = new LaxContentLengthStrategy(); this.outgoingContentStrategy = new StrictContentLengthStrategy(); this.inTransportMetrics = createTransportMetrics(); this.outTransportMetrics = createTransportMetrics(); this.connMetrics = createConnectionMetrics(this.inTransportMetrics, this.outTransportMetrics); setSession(session); this.status = ACTIVE; } private void setSession(final IOSession session) { this.session = session; this.context = new SessionHttpContext(this.session); this.session.setBufferStatus(this); this.remote = this.session.getRemoteAddress(); } /** * @since 4.1 */ protected HttpTransportMetricsImpl createTransportMetrics() { return new HttpTransportMetricsImpl(); } /** * @since 4.1 */ protected HttpConnectionMetricsImpl createConnectionMetrics(final HttpTransportMetrics inTransportMetric, final HttpTransportMetrics outTransportMetric) { return new HttpConnectionMetricsImpl(inTransportMetric, outTransportMetric); } public int getStatus() { return this.status; } public HttpContext getContext() { return this.context; } public HttpRequest getHttpRequest() { return this.request; } public HttpResponse getHttpResponse() { return this.response; } public void requestInput() { this.session.setEvent(EventMask.READ); } public void requestOutput() { this.session.setEvent(EventMask.WRITE); } public void suspendInput() { this.session.clearEvent(EventMask.READ); } public void suspendOutput() { this.session.clearEvent(EventMask.WRITE); } /** * Initializes a specific {@link ContentDecoder} implementation based on the * properties of the given {@link HttpMessage} and generates an instance of * {@link HttpEntity} matching the properties of the content decoder. * * @param message the HTTP message. * @return HTTP entity. * @throws HttpException in case of an HTTP protocol violation. */ protected HttpEntity prepareDecoder(final HttpMessage message) throws HttpException { BasicHttpEntity entity = new BasicHttpEntity(); long len = this.incomingContentStrategy.determineLength(message); this.contentDecoder = createContentDecoder(len, this.session.channel(), this.inbuf, this.inTransportMetrics); if (len == ContentLengthStrategy.CHUNKED) { entity.setChunked(true); entity.setContentLength(-1); } else if (len == ContentLengthStrategy.IDENTITY) { entity.setChunked(false); entity.setContentLength(-1); } else { entity.setChunked(false); entity.setContentLength(len); } Header contentTypeHeader = message.getFirstHeader(HTTP.CONTENT_TYPE); if (contentTypeHeader != null) { entity.setContentType(contentTypeHeader); } Header contentEncodingHeader = message.getFirstHeader(HTTP.CONTENT_ENCODING); if (contentEncodingHeader != null) { entity.setContentEncoding(contentEncodingHeader); } return entity; } /** * Factory method for {@link ContentDecoder} instances. * * @param len content length, if known, {@link ContentLengthStrategy#CHUNKED} or * {@link ContentLengthStrategy#IDENTITY}, if unknown. * @param channel the session channel. * @param buffer the session buffer. * @param metrics transport metrics. * * @return content decoder. * * @since 4.1 */ protected ContentDecoder createContentDecoder(final long len, final ReadableByteChannel channel, final SessionInputBuffer buffer, final HttpTransportMetricsImpl metrics) { if (len == ContentLengthStrategy.CHUNKED) { return new ChunkDecoder(channel, buffer, metrics); } else if (len == ContentLengthStrategy.IDENTITY) { return new IdentityDecoder(channel, buffer, metrics); } else { return new LengthDelimitedDecoder(channel, buffer, metrics, len); } } /** * Initializes a specific {@link ContentEncoder} implementation based on the * properties of the given {@link HttpMessage}. * * @param message the HTTP message. * @throws HttpException in case of an HTTP protocol violation. */ protected void prepareEncoder(final HttpMessage message) throws HttpException { long len = this.outgoingContentStrategy.determineLength(message); this.contentEncoder = createContentEncoder(len, this.session.channel(), this.outbuf, this.outTransportMetrics); } /** * Factory method for {@link ContentEncoder} instances. * * @param len content length, if known, {@link ContentLengthStrategy#CHUNKED} or * {@link ContentLengthStrategy#IDENTITY}, if unknown. * @param channel the session channel. * @param buffer the session buffer. * @param metrics transport metrics. * * @return content encoder. * * @since 4.1 */ protected ContentEncoder createContentEncoder(final long len, final WritableByteChannel channel, final SessionOutputBuffer buffer, final HttpTransportMetricsImpl metrics) { if (len == ContentLengthStrategy.CHUNKED) { return new ChunkEncoder(channel, buffer, metrics); } else if (len == ContentLengthStrategy.IDENTITY) { return new IdentityEncoder(channel, buffer, metrics); } else { return new LengthDelimitedEncoder(channel, buffer, metrics, len); } } public boolean hasBufferedInput() { return this.hasBufferedInput; } public boolean hasBufferedOutput() { return this.hasBufferedOutput; } /** * Assets if the connection is still open. * * @throws ConnectionClosedException in case the connection has already * been closed. */ protected void assertNotClosed() throws ConnectionClosedException { if (this.status != ACTIVE) { throw new ConnectionClosedException("Connection is closed"); } } public void close() throws IOException { if (this.status != ACTIVE) { return; } this.status = CLOSING; if (this.outbuf.hasData()) { this.session.setEvent(EventMask.WRITE); } else { this.session.close(); this.status = CLOSED; } } public boolean isOpen() { return this.status == ACTIVE && !this.session.isClosed(); } public boolean isStale() { return this.session.isClosed(); } public InetAddress getLocalAddress() { SocketAddress address = this.session.getLocalAddress(); if (address instanceof InetSocketAddress) { return ((InetSocketAddress) address).getAddress(); } else { return null; } } public int getLocalPort() { SocketAddress address = this.session.getLocalAddress(); if (address instanceof InetSocketAddress) { return ((InetSocketAddress) address).getPort(); } else { return -1; } } public InetAddress getRemoteAddress() { SocketAddress address = this.session.getRemoteAddress(); if (address instanceof InetSocketAddress) { return ((InetSocketAddress) address).getAddress(); } else { return null; } } public int getRemotePort() { SocketAddress address = this.session.getRemoteAddress(); if (address instanceof InetSocketAddress) { return ((InetSocketAddress) address).getPort(); } else { return -1; } } public void setSocketTimeout(int timeout) { this.session.setSocketTimeout(timeout); } public int getSocketTimeout() { return this.session.getSocketTimeout(); } public void shutdown() throws IOException { this.status = CLOSED; this.session.shutdown(); } public HttpConnectionMetrics getMetrics() { return this.connMetrics; } @Override public String toString() { StringBuffer buffer = new StringBuffer(); buffer.append("["); buffer.append(this.remote); if (this.status == CLOSED) { buffer.append("(closed)"); } buffer.append("]"); return buffer.toString(); } }