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. */ package org.apache.sling.servlethelpers; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.UnsupportedEncodingException; import javax.servlet.ServletOutputStream; import javax.servlet.WriteListener; import org.apache.commons.lang3.CharEncoding; import org.apache.commons.lang3.StringUtils; /** * Manage response body content. */ class ResponseBodySupport { private ByteArrayOutputStream outputStream; private ServletOutputStream servletOutputStream; private PrintWriter printWriter; public ResponseBodySupport() { reset(); } public void reset() { outputStream = new ByteArrayOutputStream(); servletOutputStream = null; printWriter = null; } public ServletOutputStream getOutputStream() { if (servletOutputStream == null) { servletOutputStream = new ServletOutputStream() { @Override public void write(int b) throws IOException { outputStream.write(b); } @Override public boolean isReady() { return true; } @Override public void setWriteListener(WriteListener writeListener) { throw new UnsupportedOperationException(); } }; } return servletOutputStream; } public PrintWriter getWriter(String charset) { if (printWriter == null) { try { printWriter = new PrintWriter(new OutputStreamWriter(getOutputStream(), defaultCharset(charset))); } catch (UnsupportedEncodingException ex) { throw new RuntimeException("Unsupported encoding: " + defaultCharset(charset), ex); } } return printWriter; } public byte[] getOutput() { if (servletOutputStream != null) { try { servletOutputStream.flush(); } catch (IOException ex) { // ignore } } return outputStream.toByteArray(); } public String getOutputAsString(String charset) { if (printWriter != null) { printWriter.flush(); } try { return new String(getOutput(), defaultCharset(charset)); } catch (UnsupportedEncodingException ex) { throw new RuntimeException("Unsupported encoding: " + defaultCharset(charset), ex); } } private String defaultCharset(String charset) { return StringUtils.defaultString(charset, CharEncoding.UTF_8); } }