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/* * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved. * Copyright 2004 The Apache Software Foundation * * Licensed 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 javax.servlet; import java.io.OutputStream; import java.io.IOException; import java.io.CharConversionException; import java.text.MessageFormat; import java.util.ResourceBundle; /** * Provides an output stream for sending binary data to the * client. A <code>ServletOutputStream</code> object is normally retrieved * via the {@link ServletResponse#getOutputStream} method. * * <p>This is an abstract class that the servlet container implements. * Subclasses of this class * must implement the <code>java.io.OutputStream.write(int)</code> * method. * * * @author Various * * @see ServletResponse * */ public abstract class ServletOutputStream extends OutputStream { private static final String LSTRING_FILE = "javax.servlet.LocalStrings"; private static ResourceBundle lStrings = ResourceBundle.getBundle(LSTRING_FILE); /** * * Does nothing, because this is an abstract class. * */ protected ServletOutputStream() { } /** * Writes a <code>String</code> to the client, * without a carriage return-line feed (CRLF) * character at the end. * * * @param s the <code>String</code> to send to the client * * @exception IOException if an input or output exception occurred * */ public void print(String s) throws IOException { if (s == null) s = "null"; int len = s.length(); for (int i = 0; i < len; i++) { char c = s.charAt(i); // // XXX NOTE: This is clearly incorrect for many strings, // but is the only consistent approach within the current // servlet framework. It must suffice until servlet output // streams properly encode their output. // if ((c & 0xff00) != 0) { // high order byte must be zero String errMsg = lStrings.getString("err.not_iso8859_1"); Object[] errArgs = new Object[1]; errArgs[0] = Character.valueOf(c); errMsg = MessageFormat.format(errMsg, errArgs); throw new CharConversionException(errMsg); } write(c); } } /** * Writes a <code>boolean</code> value to the client, * with no carriage return-line feed (CRLF) * character at the end. * * @param b the <code>boolean</code> value * to send to the client * * @exception IOException if an input or output exception occurred * */ public void print(boolean b) throws IOException { String msg; if (b) { msg = lStrings.getString("value.true"); } else { msg = lStrings.getString("value.false"); } print(msg); } /** * Writes a character to the client, * with no carriage return-line feed (CRLF) * at the end. * * @param c the character to send to the client * * @exception IOException if an input or output exception occurred * */ public void print(char c) throws IOException { print(String.valueOf(c)); } /** * * Writes an int to the client, * with no carriage return-line feed (CRLF) * at the end. * * @param i the int to send to the client * * @exception IOException if an input or output exception occurred * */ public void print(int i) throws IOException { print(String.valueOf(i)); } /** * * Writes a <code>long</code> value to the client, * with no carriage return-line feed (CRLF) at the end. * * @param l the <code>long</code> value * to send to the client * * @exception IOException if an input or output exception * occurred * */ public void print(long l) throws IOException { print(String.valueOf(l)); } /** * * Writes a <code>float</code> value to the client, * with no carriage return-line feed (CRLF) at the end. * * @param f the <code>float</code> value * to send to the client * * @exception IOException if an input or output exception occurred * * */ public void print(float f) throws IOException { print(String.valueOf(f)); } /** * * Writes a <code>double</code> value to the client, * with no carriage return-line feed (CRLF) at the end. * * @param d the <code>double</code> value * to send to the client * * @exception IOException if an input or output exception occurred * */ public void print(double d) throws IOException { print(String.valueOf(d)); } /** * Writes a carriage return-line feed (CRLF) * to the client. * * * * @exception IOException if an input or output exception occurred * */ public void println() throws IOException { print("\r\n"); } /** * Writes a <code>String</code> to the client, * followed by a carriage return-line feed (CRLF). * * * @param s the <code>String</code> to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(String s) throws IOException { print(s); println(); } /** * * Writes a <code>boolean</code> value to the client, * followed by a * carriage return-line feed (CRLF). * * * @param b the <code>boolean</code> value * to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(boolean b) throws IOException { print(b); println(); } /** * * Writes a character to the client, followed by a carriage * return-line feed (CRLF). * * @param c the character to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(char c) throws IOException { print(c); println(); } /** * * Writes an int to the client, followed by a * carriage return-line feed (CRLF) character. * * * @param i the int to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(int i) throws IOException { print(i); println(); } /** * * Writes a <code>long</code> value to the client, followed by a * carriage return-line feed (CRLF). * * * @param l the <code>long</code> value to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(long l) throws IOException { print(l); println(); } /** * * Writes a <code>float</code> value to the client, * followed by a carriage return-line feed (CRLF). * * @param f the <code>float</code> value * to write to the client * * * @exception IOException if an input or output exception * occurred * */ public void println(float f) throws IOException { print(f); println(); } /** * * Writes a <code>double</code> value to the client, * followed by a carriage return-line feed (CRLF). * * * @param d the <code>double</code> value * to write to the client * * @exception IOException if an input or output exception occurred * */ public void println(double d) throws IOException { print(d); println(); } /** * This method can be used to determine if data can be written without blocking. * * @return <code>true</code> if a write to this <code>ServletOutputStream</code> * will succeed, otherwise returns <code>false</code>. * * @since Servlet 3.1 */ public abstract boolean isReady(); /** * Instructs the <code>ServletOutputStream</code> to invoke the provided * {@link WriteListener} when it is possible to write * * * @param writeListener the {@link WriteListener} that should be notified * when it's possible to write * * @exception IllegalStateException if one of the following conditions is true * <ul> * <li>the associated request is neither upgraded nor the async started * <li>setWriteListener is called more than once within the scope of the same request. * </ul> * * @throws NullPointerException if writeListener is null * * @since Servlet 3.1 */ public abstract void setWriteListener(WriteListener writeListener); }