Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project 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. */ package io.netty.handler.codec.http; import io.netty.buffer.ByteBuf; import io.netty.buffer.Unpooled; import io.netty.handler.codec.DefaultHeaders.NameValidator; import io.netty.util.internal.StringUtil; import java.util.Map.Entry; /** * The default {@link LastHttpContent} implementation. */ public class DefaultLastHttpContent extends DefaultHttpContent implements LastHttpContent { private final HttpHeaders trailingHeaders; private final boolean validateHeaders; public DefaultLastHttpContent() { this(Unpooled.buffer(0)); } public DefaultLastHttpContent(ByteBuf content) { this(content, true); } public DefaultLastHttpContent(ByteBuf content, boolean validateHeaders) { super(content); trailingHeaders = new TrailingHttpHeaders(validateHeaders); this.validateHeaders = validateHeaders; } @Override public LastHttpContent copy() { return replace(content().copy()); } @Override public LastHttpContent duplicate() { return replace(content().duplicate()); } @Override public LastHttpContent retainedDuplicate() { return replace(content().retainedDuplicate()); } @Override public LastHttpContent replace(ByteBuf content) { final DefaultLastHttpContent dup = new DefaultLastHttpContent(content, validateHeaders); dup.trailingHeaders().set(trailingHeaders()); return dup; } @Override public LastHttpContent retain(int increment) { super.retain(increment); return this; } @Override public LastHttpContent retain() { super.retain(); return this; } @Override public LastHttpContent touch() { super.touch(); return this; } @Override public LastHttpContent touch(Object hint) { super.touch(hint); return this; } @Override public HttpHeaders trailingHeaders() { return trailingHeaders; } @Override public String toString() { StringBuilder buf = new StringBuilder(super.toString()); buf.append(StringUtil.NEWLINE); appendHeaders(buf); // Remove the last newline. buf.setLength(buf.length() - StringUtil.NEWLINE.length()); return buf.toString(); } private void appendHeaders(StringBuilder buf) { for (Entry<String, String> e : trailingHeaders()) { buf.append(e.getKey()); buf.append(": "); buf.append(e.getValue()); buf.append(StringUtil.NEWLINE); } } private static final class TrailingHttpHeaders extends DefaultHttpHeaders { private static final NameValidator<CharSequence> TrailerNameValidator = new NameValidator<CharSequence>() { @Override public void validateName(CharSequence name) { DefaultHttpHeaders.HttpNameValidator.validateName(name); if (HttpHeaderNames.CONTENT_LENGTH.contentEqualsIgnoreCase(name) || HttpHeaderNames.TRANSFER_ENCODING.contentEqualsIgnoreCase(name) || HttpHeaderNames.TRAILER.contentEqualsIgnoreCase(name)) { throw new IllegalArgumentException("prohibited trailing header: " + name); } } }; @SuppressWarnings({ "unchecked" }) TrailingHttpHeaders(boolean validate) { super(validate, validate ? TrailerNameValidator : NameValidator.NOT_NULL); } } }