org.fusesource.jansi.AnsiConsole Maven / Gradle / Ivy
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/*
* Copyright (C) 2009-2017 the original author(s).
*
* 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 org.fusesource.jansi;
import static org.fusesource.jansi.internal.CLibrary.STDERR_FILENO;
import static org.fusesource.jansi.internal.CLibrary.STDOUT_FILENO;
import static org.fusesource.jansi.internal.CLibrary.isatty;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.Locale;
/**
* Provides consistent access to an ANSI aware console PrintStream or an ANSI codes stripping PrintStream
* if not on a terminal (see
* Jansi native
* CLibrary isatty(int)).
* The native library used is named jansi and is loaded using HawtJNI Runtime
* Library
*
* @author Hiram Chirino
* @since 1.0
* @see #systemInstall()
* @see #wrapPrintStream(PrintStream, int) wrapPrintStream(PrintStream, int) for more details on ANSI mode selection
*/
public class AnsiConsole {
public static final PrintStream system_out = System.out;
public static final PrintStream out;
public static final PrintStream system_err = System.err;
public static final PrintStream err;
static final boolean IS_WINDOWS = System.getProperty("os.name").toLowerCase(Locale.ENGLISH).contains("win");
static final boolean IS_CYGWIN = IS_WINDOWS
&& System.getenv("PWD") != null
&& System.getenv("PWD").startsWith("/")
&& !"cygwin".equals(System.getenv("TERM"));
static final boolean IS_MINGW_XTERM = IS_WINDOWS
&& System.getenv("MSYSTEM") != null
&& System.getenv("MSYSTEM").startsWith("MINGW")
&& "xterm".equals(System.getenv("TERM"));
private static JansiOutputType jansiOutputType;
static final JansiOutputType JANSI_STDOUT_TYPE;
static final JansiOutputType JANSI_STDERR_TYPE;
static {
out = wrapSystemOut(system_out);
JANSI_STDOUT_TYPE = jansiOutputType;
err = wrapSystemErr(system_err);
JANSI_STDERR_TYPE = jansiOutputType;
}
private static int installed;
private AnsiConsole() {
}
@Deprecated
public static OutputStream wrapOutputStream(final OutputStream stream) {
try {
return wrapOutputStream(stream, STDOUT_FILENO);
} catch (Throwable ignore) {
return wrapOutputStream(stream, 1);
}
}
public static PrintStream wrapSystemOut(final PrintStream ps) {
try {
return wrapPrintStream(ps, STDOUT_FILENO);
} catch (Throwable ignore) {
return wrapPrintStream(ps, 1);
}
}
@Deprecated
public static OutputStream wrapErrorOutputStream(final OutputStream stream) {
try {
return wrapOutputStream(stream, STDERR_FILENO);
} catch (Throwable ignore) {
return wrapOutputStream(stream, 2);
}
}
public static PrintStream wrapSystemErr(final PrintStream ps) {
try {
return wrapPrintStream(ps, STDERR_FILENO);
} catch (Throwable ignore) {
return wrapPrintStream(ps, 2);
}
}
@Deprecated
public static OutputStream wrapOutputStream(final OutputStream stream, int fileno) {
// If the jansi.passthrough property is set, then don't interpret
// any of the ansi sequences.
if (Boolean.getBoolean("jansi.passthrough")) {
jansiOutputType = JansiOutputType.PASSTHROUGH;
return stream;
}
// If the jansi.strip property is set, then we just strip the
// the ansi escapes.
if (Boolean.getBoolean("jansi.strip")) {
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiOutputStream(stream);
}
if (IS_WINDOWS && !IS_CYGWIN && !IS_MINGW_XTERM) {
// On windows we know the console does not interpret ANSI codes..
try {
jansiOutputType = JansiOutputType.WINDOWS;
return new WindowsAnsiOutputStream(stream, fileno == STDOUT_FILENO);
} catch (Throwable ignore) {
// this happens when JNA is not in the path.. or
// this happens when the stdout is being redirected to a file.
}
// Use the ANSIOutputStream to strip out the ANSI escape sequences.
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiOutputStream(stream);
}
// We must be on some Unix variant, including Cygwin or MSYS(2) on Windows...
try {
// If the jansi.force property is set, then we force to output
// the ansi escapes for piping it into ansi color aware commands (e.g. less -r)
boolean forceColored = Boolean.getBoolean("jansi.force");
// If we can detect that stdout is not a tty.. then setup
// to strip the ANSI sequences..
if (!forceColored && isatty(fileno) == 0) {
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiOutputStream(stream);
}
} catch (Throwable ignore) {
// These errors happen if the JNI lib is not available for your platform.
// But since we are on ANSI friendly platform, assume the user is on the console.
}
// By default we assume your Unix tty can handle ANSI codes.
// Just wrap it up so that when we get closed, we reset the
// attributes.
jansiOutputType = JansiOutputType.RESET_ANSI_AT_CLOSE;
return new FilterOutputStream(stream) {
@Override
public void close() throws IOException {
write(AnsiOutputStream.RESET_CODE);
flush();
super.close();
}
};
}
/**
* Wrap PrintStream applying rules in following order:
* - if
jansi.passthrough is true, don't wrap but just passthrough (console is
* expected to natively support ANSI escape codes),
* - if
jansi.strip is true, just strip ANSI escape codes inconditionally,
* - if OS is Windows and terminal is not Cygwin or Mingw, wrap as WindowsAnsiPrintStream to process ANSI escape codes,
* - if file descriptor is a terminal (see
isatty(int)) or jansi.force is true,
* just passthrough,
* - else strip ANSI escape codes (not a terminal).
*
*
* @param ps original PrintStream to wrap
* @param fileno file descriptor
* @return wrapped PrintStream depending on OS and system properties
* @since 1.17
*/
public static PrintStream wrapPrintStream(final PrintStream ps, int fileno) {
// If the jansi.passthrough property is set, then don't interpret
// any of the ansi sequences.
if (Boolean.getBoolean("jansi.passthrough")) {
jansiOutputType = JansiOutputType.PASSTHROUGH;
return ps;
}
// If the jansi.strip property is set, then we just strip the
// the ansi escapes.
if (Boolean.getBoolean("jansi.strip")) {
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiPrintStream(ps);
}
if (IS_WINDOWS && !IS_CYGWIN && !IS_MINGW_XTERM) {
// On windows we know the console does not interpret ANSI codes..
try {
jansiOutputType = JansiOutputType.WINDOWS;
return new WindowsAnsiPrintStream(ps, fileno == STDOUT_FILENO);
} catch (Throwable ignore) {
// this happens when JNA is not in the path.. or
// this happens when the stdout is being redirected to a file.
}
// Use the AnsiPrintStream to strip out the ANSI escape sequences.
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiPrintStream(ps);
}
// We must be on some Unix variant, including Cygwin or MSYS(2) on Windows...
try {
// If the jansi.force property is set, then we force to output
// the ansi escapes for piping it into ansi color aware commands (e.g. less -r)
boolean forceColored = Boolean.getBoolean("jansi.force");
// If we can detect that stdout is not a tty.. then setup
// to strip the ANSI sequences..
if (!forceColored && isatty(fileno) == 0) {
jansiOutputType = JansiOutputType.STRIP_ANSI;
return new AnsiPrintStream(ps);
}
} catch (Throwable ignore) {
// These errors happen if the JNI lib is not available for your platform.
// But since we are on ANSI friendly platform, assume the user is on the console.
}
// By default we assume your Unix tty can handle ANSI codes.
// Just wrap it up so that when we get closed, we reset the
// attributes.
jansiOutputType = JansiOutputType.RESET_ANSI_AT_CLOSE;
return new FilterPrintStream(ps) {
@Override
public void close() {
ps.print(AnsiPrintStream.RESET_CODE);
ps.flush();
super.close();
}
};
}
/**
* If the standard out natively supports ANSI escape codes, then this just
* returns System.out, otherwise it will provide an ANSI aware PrintStream
* which strips out the ANSI escape sequences or which implement the escape
* sequences.
*
* @return a PrintStream which is ANSI aware.
* @see #wrapPrintStream(PrintStream, int)
*/
public static PrintStream out() {
return out;
}
/**
* If the standard out natively supports ANSI escape codes, then this just
* returns System.err, otherwise it will provide an ANSI aware PrintStream
* which strips out the ANSI escape sequences or which implement the escape
* sequences.
*
* @return a PrintStream which is ANSI aware.
* @see #wrapPrintStream(PrintStream, int)
*/
public static PrintStream err() {
return err;
}
/**
* Install AnsiConsole.out to System.out and
* AnsiConsole.err to System.err.
* @see #systemUninstall()
*/
synchronized static public void systemInstall() {
installed++;
if (installed == 1) {
System.setOut(out);
System.setErr(err);
}
}
/**
* undo a previous {@link #systemInstall()}. If {@link #systemInstall()} was called
* multiple times, {@link #systemUninstall()} must be called the same number of times before
* it is actually uninstalled.
*/
synchronized public static void systemUninstall() {
installed--;
if (installed == 0) {
System.setOut(system_out);
System.setErr(system_err);
}
}
/**
* Type of output installed by AnsiConsole.
*/
enum JansiOutputType {
PASSTHROUGH("just pass through, ANSI escape codes are supposed to be supported by terminal"),
RESET_ANSI_AT_CLOSE("like pass through but reset ANSI attributes when closing the stream"),
STRIP_ANSI("strip ANSI escape codes, for example when output is not a terminal"),
WINDOWS("detect ANSI escape codes and transform Jansi-supported ones into a Windows API to get desired effect" +
" (since ANSI escape codes are not natively supported by Windows terminals like cmd.exe or PowerShell)");
private final String description;
private JansiOutputType(String description) {
this.description = description;
}
String getDescription() {
return description;
}
};
}