jakarta.servlet.ServletOutputStream Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2022 Oracle and/or its affiliates and others.
* 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 jakarta.servlet;
import java.io.CharConversionException;
import java.io.IOException;
import java.io.OutputStream;
import java.text.MessageFormat;
import java.util.ResourceBundle;
/**
* Provides an output stream for sending binary data to the client. A ServletOutputStream object is
* normally retrieved via the {@link ServletResponse#getOutputStream} method.
*
*
* This is an abstract class that the servlet container implements. Subclasses of this class must implement the
* java.io.OutputStream.write(int) method.
*
*
* @author Various
*
* @see ServletResponse
*
*/
public abstract class ServletOutputStream extends OutputStream {
private static final String LSTRING_FILE = "jakarta.servlet.LocalStrings";
private static ResourceBundle lStrings = ResourceBundle.getBundle(LSTRING_FILE);
/**
*
* Does nothing, because this is an abstract class.
*
*/
protected ServletOutputStream() {
}
/**
* Writes a String to the client, without a carriage return-line feed (CRLF) character at the end.
*
*
* @param s the String 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();
byte[] out = new byte[len];
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);
}
out[i] = (byte) (0xff & c);
}
write(out, 0, len);
}
/**
* Writes a boolean value to the client, with no carriage return-line feed (CRLF) character at the end.
*
* @param b the boolean value to send to the client
*
* @exception IOException if an input or output exception occurred
*
*/
public void print(boolean b) throws IOException {
print(lStrings.getString(b ? "value.true" : "value.false"));
}
/**
* 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 long value to the client, with no carriage return-line feed (CRLF) at the end.
*
* @param l the long 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 float value to the client, with no carriage return-line feed (CRLF) at the end.
*
* @param f the float 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 double value to the client, with no carriage return-line feed (CRLF) at the end.
*
* @param d the double 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 String to the client, followed by a carriage return-line feed (CRLF).
*
*
* @param s the String to write to the client
*
* @exception IOException if an input or output exception occurred
*
*/
public void println(String s) throws IOException {
print(s == null ? "null\r\n" : (s + "\r\n"));
}
/**
*
* Writes a boolean value to the client, followed by a carriage return-line feed (CRLF).
*
*
* @param b the boolean value to write to the client
*
* @exception IOException if an input or output exception occurred
*
*/
public void println(boolean b) throws IOException {
println(lStrings.getString(b ? "value.true" : "value.false"));
}
/**
*
* 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 {
println(String.valueOf(c));
}
/**
*
* 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 {
println(String.valueOf(i));
}
/**
*
* Writes a long value to the client, followed by a carriage return-line feed (CRLF).
*
*
* @param l the long value to write to the client
*
* @exception IOException if an input or output exception occurred
*
*/
public void println(long l) throws IOException {
println(String.valueOf(l));
}
/**
*
* Writes a float value to the client, followed by a carriage return-line feed (CRLF).
*
* @param f the float value to write to the client
*
*
* @exception IOException if an input or output exception occurred
*
*/
public void println(float f) throws IOException {
println(String.valueOf(f));
}
/**
*
* Writes a double value to the client, followed by a carriage return-line feed (CRLF).
*
*
* @param d the double value to write to the client
*
* @exception IOException if an input or output exception occurred
*
*/
public void println(double d) throws IOException {
println(String.valueOf(d));
}
/**
* Returns true if data can be written without blocking else returns false.
*
* If this method returns false and a {@link WriteListener} has been set with {@link #setWriteListener(WriteListener)},
* then container will subsequently invoke {@link WriteListener#onWritePossible()} once a write operation becomes
* possible without blocking. Other than the initial call, {@link WriteListener#onWritePossible()} will only be called
* if and only if this method is called and returns false.
*
* @return true if data can be written without blocking, otherwise returns false.
* @see WriteListener
* @since Servlet 3.1
*/
public abstract boolean isReady();
/**
* Instructs the ServletOutputStream 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
*
* - the associated request is neither upgraded nor the async started
*
- setWriteListener is called more than once within the scope of the same request.
*
*
* @throws NullPointerException if writeListener is null
*
* @since Servlet 3.1
*/
public abstract void setWriteListener(WriteListener writeListener);
}