Java tutorial
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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 org.apache.http.HttpEntity; import org.apache.http.HttpEntityEnclosingRequest; import org.apache.http.HttpException; import org.apache.http.HttpRequest; import org.apache.http.HttpRequestFactory; import org.apache.http.HttpResponse; import org.apache.http.impl.nio.codecs.DefaultHttpRequestParser; import org.apache.http.impl.nio.codecs.DefaultHttpResponseWriter; import org.apache.http.nio.NHttpMessageParser; import org.apache.http.nio.NHttpMessageWriter; import org.apache.http.nio.NHttpServerConnection; import org.apache.http.nio.NHttpServerIOTarget; import org.apache.http.nio.NHttpServiceHandler; import org.apache.http.nio.reactor.EventMask; import org.apache.http.nio.reactor.IOSession; 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.HttpParams; /** * Default implementation of the {@link NHttpServerConnection} interface. * <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> * <li>{@link org.apache.http.params.CoreConnectionPNames#MAX_HEADER_COUNT}</li> * <li>{@link org.apache.http.params.CoreConnectionPNames#MAX_LINE_LENGTH}</li> * </ul> * * @since 4.0 */ public class DefaultNHttpServerConnection extends NHttpConnectionBase implements NHttpServerIOTarget { protected final NHttpMessageParser<HttpRequest> requestParser; protected final NHttpMessageWriter<HttpResponse> responseWriter; /** * Creates a new instance of this class given the underlying I/O session. * * @param session the underlying I/O session. * @param requestFactory HTTP request factory. * @param allocator byte buffer allocator. * @param params HTTP parameters. */ public DefaultNHttpServerConnection(final IOSession session, final HttpRequestFactory requestFactory, final ByteBufferAllocator allocator, final HttpParams params) { super(session, allocator, params); if (requestFactory == null) { throw new IllegalArgumentException("Request factory may not be null"); } this.requestParser = createRequestParser(this.inbuf, requestFactory, params); this.responseWriter = createResponseWriter(this.outbuf, params); } /** * Creates an instance of {@link NHttpMessageParser} to be used * by this connection for parsing incoming {@link HttpRequest} messages. * <p> * This method can be overridden in a super class in order to provide * a different implementation of the {@link NHttpMessageParser} interface. * * @return HTTP response parser. */ protected NHttpMessageParser<HttpRequest> createRequestParser(final SessionInputBuffer buffer, final HttpRequestFactory requestFactory, final HttpParams params) { // override in derived class to specify a line parser return new DefaultHttpRequestParser(buffer, null, requestFactory, params); } /** * Creates an instance of {@link NHttpMessageWriter} to be used * by this connection for writing out outgoing {@link HttpResponse} * messages. * <p> * This method can be overridden by a super class in order to provide * a different implementation of the {@link NHttpMessageWriter} interface. * * @return HTTP response parser. */ protected NHttpMessageWriter<HttpResponse> createResponseWriter(final SessionOutputBuffer buffer, final HttpParams params) { // override in derived class to specify a line formatter return new DefaultHttpResponseWriter(buffer, null, params); } public void resetInput() { this.request = null; this.contentDecoder = null; this.requestParser.reset(); } public void resetOutput() { this.response = null; this.contentEncoder = null; this.responseWriter.reset(); } public void consumeInput(final NHttpServiceHandler handler) { if (this.status != ACTIVE) { this.session.clearEvent(EventMask.READ); return; } try { if (this.request == null) { int bytesRead; do { bytesRead = this.requestParser.fillBuffer(this.session.channel()); if (bytesRead > 0) { this.inTransportMetrics.incrementBytesTransferred(bytesRead); } this.request = this.requestParser.parse(); } while (bytesRead > 0 && this.request == null); if (this.request != null) { if (this.request instanceof HttpEntityEnclosingRequest) { // Receive incoming entity HttpEntity entity = prepareDecoder(this.request); ((HttpEntityEnclosingRequest) this.request).setEntity(entity); } this.connMetrics.incrementRequestCount(); handler.requestReceived(this); if (this.contentDecoder == null) { // No request entity is expected // Ready to receive a new request resetInput(); } } if (bytesRead == -1) { close(); } } if (this.contentDecoder != null) { handler.inputReady(this, this.contentDecoder); if (this.contentDecoder.isCompleted()) { // Request entity received // Ready to receive a new request resetInput(); } } } catch (IOException ex) { handler.exception(this, ex); } catch (HttpException ex) { resetInput(); handler.exception(this, ex); } finally { // Finally set buffered input flag this.hasBufferedInput = this.inbuf.hasData(); } } public void produceOutput(final NHttpServiceHandler handler) { try { if (this.outbuf.hasData()) { int bytesWritten = this.outbuf.flush(this.session.channel()); if (bytesWritten > 0) { this.outTransportMetrics.incrementBytesTransferred(bytesWritten); } } if (!this.outbuf.hasData()) { if (this.status == CLOSING) { this.session.close(); this.status = CLOSED; resetOutput(); return; } else { if (this.contentEncoder != null) { handler.outputReady(this, this.contentEncoder); if (this.contentEncoder.isCompleted()) { resetOutput(); } } } if (this.contentEncoder == null && !this.outbuf.hasData()) { if (this.status == CLOSING) { this.session.close(); this.status = CLOSED; } if (this.status != CLOSED) { this.session.clearEvent(EventMask.WRITE); handler.responseReady(this); } } } } catch (IOException ex) { handler.exception(this, ex); } finally { // Finally set the buffered output flag this.hasBufferedOutput = this.outbuf.hasData(); } } public void submitResponse(final HttpResponse response) throws IOException, HttpException { if (response == null) { throw new IllegalArgumentException("HTTP response may not be null"); } assertNotClosed(); if (this.response != null) { throw new HttpException("Response already submitted"); } this.responseWriter.write(response); this.hasBufferedOutput = this.outbuf.hasData(); if (response.getStatusLine().getStatusCode() >= 200) { this.connMetrics.incrementResponseCount(); if (response.getEntity() != null) { this.response = response; prepareEncoder(response); } } this.session.setEvent(EventMask.WRITE); } public boolean isResponseSubmitted() { return this.response != null; } }