org.jline.terminal.TerminalBuilder Maven / Gradle / Ivy
/*
* Copyright (c) 2002-2019, the original author or authors.
*
* This software is distributable under the BSD license. See the terms of the
* BSD license in the documentation provided with this software.
*
* https://opensource.org/licenses/BSD-3-Clause
*/
package org.jline.terminal;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.Method;
import java.nio.charset.Charset;
import java.nio.charset.UnsupportedCharsetException;
import java.util.Optional;
import java.util.ServiceLoader;
import java.util.concurrent.atomic.AtomicReference;
import org.jline.terminal.impl.AbstractPosixTerminal;
import org.jline.terminal.impl.AbstractTerminal;
import org.jline.terminal.impl.DumbTerminal;
import org.jline.terminal.impl.ExecPty;
import org.jline.terminal.impl.ExternalTerminal;
import org.jline.terminal.impl.PosixPtyTerminal;
import org.jline.terminal.impl.PosixSysTerminal;
import org.jline.terminal.spi.JansiSupport;
import org.jline.terminal.spi.JnaSupport;
import org.jline.terminal.spi.Pty;
import org.jline.utils.Log;
import org.jline.utils.OSUtils;
/**
* Builder class to create terminals.
*/
public final class TerminalBuilder {
//
// System properties
//
public static final String PROP_ENCODING = "org.jline.terminal.encoding";
public static final String PROP_CODEPAGE = "org.jline.terminal.codepage";
public static final String PROP_TYPE = "org.jline.terminal.type";
public static final String PROP_JNA = "org.jline.terminal.jna";
public static final String PROP_JANSI = "org.jline.terminal.jansi";
public static final String PROP_EXEC = "org.jline.terminal.exec";
public static final String PROP_DUMB = "org.jline.terminal.dumb";
public static final String PROP_DUMB_COLOR = "org.jline.terminal.dumb.color";
//
// Other system properties controlling various jline parts
//
public static final String PROP_NON_BLOCKING_READS = "org.jline.terminal.pty.nonBlockingReads";
public static final String PROP_COLOR_DISTANCE = "org.jline.utils.colorDistance";
public static final String PROP_DISABLE_ALTERNATE_CHARSET = "org.jline.utils.disableAlternateCharset";
/**
* Returns the default system terminal.
* Terminals should be closed properly using the {@link Terminal#close()}
* method in order to restore the original terminal state.
*
*
* This call is equivalent to:
* builder().build()
*
*
* @return the default system terminal
* @throws IOException if an error occurs
*/
public static Terminal terminal() throws IOException {
return builder().build();
}
/**
* Creates a new terminal builder instance.
*
* @return a builder
*/
public static TerminalBuilder builder() {
return new TerminalBuilder();
}
private static final AtomicReference SYSTEM_TERMINAL = new AtomicReference<>();
private static final AtomicReference TERMINAL_OVERRIDE = new AtomicReference<>();
private String name;
private InputStream in;
private OutputStream out;
private String type;
private Charset encoding;
private int codepage;
private Boolean system;
private Boolean jna;
private Boolean jansi;
private Boolean exec;
private Boolean dumb;
private Attributes attributes;
private Size size;
private boolean nativeSignals = false;
private Terminal.SignalHandler signalHandler = Terminal.SignalHandler.SIG_DFL;
private boolean paused = false;
private TerminalBuilder() {
}
public TerminalBuilder name(String name) {
this.name = name;
return this;
}
public TerminalBuilder streams(InputStream in, OutputStream out) {
this.in = in;
this.out = out;
return this;
}
public TerminalBuilder system(boolean system) {
this.system = system;
return this;
}
public TerminalBuilder jna(boolean jna) {
this.jna = jna;
return this;
}
public TerminalBuilder jansi(boolean jansi) {
this.jansi = jansi;
return this;
}
public TerminalBuilder exec(boolean exec) {
this.exec = exec;
return this;
}
public TerminalBuilder dumb(boolean dumb) {
this.dumb = dumb;
return this;
}
public TerminalBuilder type(String type) {
this.type = type;
return this;
}
/**
* Set the encoding to use for reading/writing from the console.
* If {@code null} (the default value), JLine will automatically select
* a {@link Charset}, usually the default system encoding. However,
* on some platforms (e.g. Windows) it may use a different one depending
* on the {@link Terminal} implementation.
*
* Use {@link Terminal#encoding()} to get the {@link Charset} that
* should be used for a {@link Terminal}.
*
* @param encoding The encoding to use or null to automatically select one
* @return The builder
* @throws UnsupportedCharsetException If the given encoding is not supported
* @see Terminal#encoding()
*/
public TerminalBuilder encoding(String encoding) throws UnsupportedCharsetException {
return encoding(encoding != null ? Charset.forName(encoding) : null);
}
/**
* Set the {@link Charset} to use for reading/writing from the console.
* If {@code null} (the default value), JLine will automatically select
* a {@link Charset}, usually the default system encoding. However,
* on some platforms (e.g. Windows) it may use a different one depending
* on the {@link Terminal} implementation.
*
* Use {@link Terminal#encoding()} to get the {@link Charset} that
* should be used to read/write from a {@link Terminal}.
*
* @param encoding The encoding to use or null to automatically select one
* @return The builder
* @see Terminal#encoding()
*/
public TerminalBuilder encoding(Charset encoding) {
this.encoding = encoding;
return this;
}
/**
* @param codepage the codepage
* @return The builder
* @deprecated JLine now writes Unicode output independently from the selected
* code page. Using this option will only make it emulate the selected code
* page for {@link Terminal#input()} and {@link Terminal#output()}.
*/
@Deprecated
public TerminalBuilder codepage(int codepage) {
this.codepage = codepage;
return this;
}
/**
* Attributes to use when creating a non system terminal,
* i.e. when the builder has been given the input and
* outut streams using the {@link #streams(InputStream, OutputStream)} method
* or when {@link #system(boolean)} has been explicitely called with
* false
.
*
* @param attributes the attributes to use
* @return The builder
* @see #size(Size)
* @see #system(boolean)
*/
public TerminalBuilder attributes(Attributes attributes) {
this.attributes = attributes;
return this;
}
/**
* Initial size to use when creating a non system terminal,
* i.e. when the builder has been given the input and
* outut streams using the {@link #streams(InputStream, OutputStream)} method
* or when {@link #system(boolean)} has been explicitely called with
* false
.
*
* @param size the initial size
* @return The builder
* @see #attributes(Attributes)
* @see #system(boolean)
*/
public TerminalBuilder size(Size size) {
this.size = size;
return this;
}
public TerminalBuilder nativeSignals(boolean nativeSignals) {
this.nativeSignals = nativeSignals;
return this;
}
public TerminalBuilder signalHandler(Terminal.SignalHandler signalHandler) {
this.signalHandler = signalHandler;
return this;
}
/**
* Initial paused state of the terminal (defaults to false).
* By default, the terminal is started, but in some cases,
* one might want to make sure the input stream is not consumed
* before needed, in which case the terminal needs to be created
* in a paused state.
* @param paused the initial paused state
* @return The builder
* @see Terminal#pause()
*/
public TerminalBuilder paused(boolean paused) {
this.paused = paused;
return this;
}
public Terminal build() throws IOException {
Terminal override = TERMINAL_OVERRIDE.get();
Terminal terminal = override != null ? override : doBuild();
if (override != null) {
Log.debug(() -> "Overriding terminal with global value set by TerminalBuilder.setTerminalOverride");
}
Log.debug(() -> "Using terminal " + terminal.getClass().getSimpleName());
if (terminal instanceof AbstractPosixTerminal) {
Log.debug(() -> "Using pty " + ((AbstractPosixTerminal) terminal).getPty().getClass().getSimpleName());
}
return terminal;
}
private Terminal doBuild() throws IOException {
String name = this.name;
if (name == null) {
name = "JLine terminal";
}
Charset encoding = this.encoding;
if (encoding == null) {
String charsetName = System.getProperty(PROP_ENCODING);
if (charsetName != null && Charset.isSupported(charsetName)) {
encoding = Charset.forName(charsetName);
}
}
int codepage = this.codepage;
if (codepage <= 0) {
String str = System.getProperty(PROP_CODEPAGE);
if (str != null) {
codepage = Integer.parseInt(str);
}
}
String type = this.type;
if (type == null) {
type = System.getProperty(PROP_TYPE);
}
if (type == null) {
type = System.getenv("TERM");
}
Boolean jna = this.jna;
if (jna == null) {
jna = getBoolean(PROP_JNA, true);
}
Boolean jansi = this.jansi;
if (jansi == null) {
jansi = getBoolean(PROP_JANSI, true);
}
Boolean exec = this.exec;
if (exec == null) {
exec = getBoolean(PROP_EXEC, true);
}
Boolean dumb = this.dumb;
if (dumb == null) {
dumb = getBoolean(PROP_DUMB, null);
}
if ((system != null && system) || (system == null && in == null && out == null)) {
if (attributes != null || size != null) {
Log.warn("Attributes and size fields are ignored when creating a system terminal");
}
IllegalStateException exception = new IllegalStateException("Unable to create a system terminal");
Terminal terminal = null;
if (OSUtils.IS_WINDOWS) {
boolean ansiPassThrough = OSUtils.IS_CONEMU;
boolean winConsole = true;
if (terminal == null && jna) {
try {
JnaSupport support = load(JnaSupport.class);
winConsole = support.isWindowsConsole();
terminal = support.winSysTerminal(name, type, ansiPassThrough, encoding, codepage, nativeSignals, signalHandler, paused);
} catch (Throwable t) {
Log.debug("Error creating JNA based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
if (terminal == null && jansi) {
try {
JansiSupport support = load(JansiSupport.class);
winConsole = support.isWindowsConsole();
terminal = support.winSysTerminal(name, type, ansiPassThrough, encoding, codepage, nativeSignals, signalHandler, paused);
} catch (Throwable t) {
Log.debug("Error creating JANSI based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
//
// Cygwin support
//
if (terminal == null && exec && (OSUtils.IS_CYGWIN || OSUtils.IS_MSYSTEM) && winConsole) {
try {
Pty pty = ExecPty.current();
// Cygwin defaults to XTERM, but actually supports 256 colors,
// so if the value comes from the environment, change it to xterm-256color
if ("xterm".equals(type) && this.type == null && System.getProperty(PROP_TYPE) == null) {
type = "xterm-256color";
}
terminal = new PosixSysTerminal(name, type, pty, encoding, nativeSignals, signalHandler);
} catch (IOException e) {
// Ignore if not a tty
Log.debug("Error creating EXEC based terminal: ", e.getMessage(), e);
exception.addSuppressed(e);
}
}
if (terminal == null && !jna && !jansi && (dumb == null || !dumb)) {
throw new IllegalStateException("Unable to create a system terminal. On windows, either "
+ "JNA or JANSI library is required. Make sure to add one of those in the classpath.");
}
} else {
if (terminal == null && jna) {
try {
Pty pty = load(JnaSupport.class).current();
terminal = new PosixSysTerminal(name, type, pty, encoding, nativeSignals, signalHandler);
} catch (Throwable t) {
// ignore
Log.debug("Error creating JNA based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
if (terminal == null && jansi) {
try {
Pty pty = load(JansiSupport.class).current();
terminal = new PosixSysTerminal(name, type, pty, encoding, nativeSignals, signalHandler);
} catch (Throwable t) {
Log.debug("Error creating JANSI based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
if (terminal == null && exec) {
try {
Pty pty = ExecPty.current();
terminal = new PosixSysTerminal(name, type, pty, encoding, nativeSignals, signalHandler);
} catch (Throwable t) {
// Ignore if not a tty
Log.debug("Error creating EXEC based terminal: ", t.getMessage(), t);
exception.addSuppressed(t);
}
}
}
if (terminal instanceof AbstractTerminal) {
AbstractTerminal t = (AbstractTerminal) terminal;
if (SYSTEM_TERMINAL.compareAndSet(null, t)) {
t.setOnClose(new Runnable() {
@Override
public void run() {
SYSTEM_TERMINAL.compareAndSet(t, null);
}
});
} else {
exception.addSuppressed(new IllegalStateException("A system terminal is already running. " +
"Make sure to use the created system Terminal on the LineReaderBuilder if you're using one " +
"or that previously created system Terminals have been correctly closed."));
terminal.close();
terminal = null;
}
}
if (terminal == null && (dumb == null || dumb)) {
// forced colored dumb terminal
boolean color = getBoolean(PROP_DUMB_COLOR, false);
// detect emacs using the env variable
if (!color) {
color = System.getenv("INSIDE_EMACS") != null;
}
// detect Intellij Idea
if (!color) {
String command = getParentProcessCommand();
color = command != null && command.contains("idea");
}
if (!color && dumb == null) {
if (Log.isDebugEnabled()) {
Log.warn("Creating a dumb terminal", exception);
} else {
Log.warn("Unable to create a system terminal, creating a dumb terminal (enable debug logging for more information)");
}
}
terminal = new DumbTerminal(name, color ? Terminal.TYPE_DUMB_COLOR : Terminal.TYPE_DUMB,
new FileInputStream(FileDescriptor.in),
new FileOutputStream(FileDescriptor.out),
encoding, signalHandler);
}
if (terminal == null) {
throw exception;
}
return terminal;
} else {
if (jna) {
try {
Pty pty = load(JnaSupport.class).open(attributes, size);
return new PosixPtyTerminal(name, type, pty, in, out, encoding, signalHandler, paused);
} catch (Throwable t) {
Log.debug("Error creating JNA based terminal: ", t.getMessage(), t);
}
}
if (jansi) {
try {
Pty pty = load(JansiSupport.class).open(attributes, size);
return new PosixPtyTerminal(name, type, pty, in, out, encoding, signalHandler, paused);
} catch (Throwable t) {
Log.debug("Error creating JANSI based terminal: ", t.getMessage(), t);
}
}
return new ExternalTerminal(name, type, in, out, encoding, signalHandler, paused, attributes, size);
}
}
private static String getParentProcessCommand() {
try {
Class> phClass = Class.forName("java.lang.ProcessHandle");
Object current = phClass.getMethod("current").invoke(null);
Object parent = ((Optional>) phClass.getMethod("parent").invoke(current)).orElse(null);
Method infoMethod = phClass.getMethod("info");
Object info = infoMethod.invoke(parent);
Object command = ((Optional>) infoMethod.getReturnType().getMethod("command").invoke(info)).orElse(null);
return (String) command;
} catch (Throwable t) {
return null;
}
}
private static Boolean getBoolean(String name, Boolean def) {
try {
String str = System.getProperty(name);
if (str != null) {
return Boolean.parseBoolean(str);
}
} catch (IllegalArgumentException | NullPointerException e) {
}
return def;
}
private S load(Class clazz) {
return ServiceLoader.load(clazz, clazz.getClassLoader()).iterator().next();
}
/**
* Allows an application to override the result of {@link #build()}. The
* intended use case is to allow a container or server application to control
* an embedded application that uses a LineReader that uses Terminal
* constructed with TerminalBuilder.build but provides no public api for setting
* the LineReader
of the {@link Terminal}. For example, the sbt
* build tool uses a LineReader
to implement an interactive shell.
* One of its supported commands is console
which invokes
* the scala REPL. The scala REPL also uses a LineReader
and it
* is necessary to override the {@link Terminal} used by the the REPL to
* share the same {@link Terminal} instance used by sbt.
*
*
* When this method is called with a non-null {@link Terminal}, all subsequent
* calls to {@link #build()} will return the provided {@link Terminal} regardless
* of how the {@link TerminalBuilder} was constructed. The default behavior
* of {@link TerminalBuilder} can be restored by calling setTerminalOverride
* with a null {@link Terminal}
*
*
*
* Usage of setTerminalOverride should be restricted to cases where it
* isn't possible to update the api of the nested application to accept
* a {@link Terminal instance}.
*
*
* @param terminal the {@link Terminal} to globally override
*/
@Deprecated
public static final void setTerminalOverride(final Terminal terminal) {
TERMINAL_OVERRIDE.set(terminal);
}
}