/*
* Copyright 2010 dorkbox, llc
*
* 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 dorkbox.executor;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.InputStream;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
/**
* If you want to save off the output from the process, set a PrintStream to the following:
* {@code
*
* ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream(8196);
* PrintStream outputStream = new PrintStream(byteArrayOutputStream);
* ...
*
* String output = ShellProcessBuilder.getOutput(byteArrayOutputStream);
* }
*/
@SuppressWarnings({"UnusedReturnValue", "unused", "ManualArrayToCollectionCopy", "UseBulkOperation", "Convert2Diamond", "Convert2Lambda",
"Anonymous2MethodRef", "WeakerAccess"})
public
class ShellExecutor {
// TODO: Add the ability to get the process PID via java for mac/windows/linux. Linux is avail from jvm, windows needs JNA
static final String LINE_SEPARATOR = System.getProperty("line.separator");
static final boolean isWindows;
static final boolean isMacOsX;
static {
String osName = System.getProperty("os.name");
isWindows = osName.startsWith("windows");
isMacOsX = osName.startsWith("mac") || osName.startsWith("darwin");
}
private static String defaultShell = null;
private final PrintStream outputStream;
private final PrintStream outputErrorStream;
private final InputStream inputStream;
protected List arguments = new ArrayList();
private Map environment = null;
private String workingDirectory = null;
private String executableName = null;
private String executableDirectory = null;
private Process process = null;
private ProcessProxy writeToProcess_input = null;
private ProcessProxy readFromProcess_output = null;
private ProcessProxy readFromProcess_error = null;
private boolean createReadWriterThreads = false;
private boolean executeAsShell;
private String pipeToNullString = "";
private ByteArrayOutputStream byteArrayOutputStream;
private List fullCommand;
/**
* Gets the version number.
*/
public static
String getVersion() {
return "1.0";
}
/**
* This is a convenience method to easily create a default process. Will block until the process is finished running
*
* @param executableName the name of the executable to run
* @param args the arguments for the executable
*
* @return true if the process ran successfully (exit value was 0), otherwise false
*/
public static boolean run(String executableName, String... args) {
ShellExecutor shell = new ShellExecutor();
shell.setExecutable(executableName);
shell.addArguments(args);
// blocks until finished
return shell.start() == 0;
}
/**
* This is a convenience method to easily create a default process. Will immediately return, and does not wait for the process to finish
*
* @param executableName the name of the executable to run
* @param args the arguments for the executable
*
* @return true if the process ran successfully (exit value was 0), otherwise false
*/
public static
boolean runShell(String executableName, String... args) {
ShellExecutor shell = new ShellExecutor();
shell.setExecutable(executableName);
shell.addArguments(args);
shell.executeAsShellCommand();
// blocks until finished
return shell.start() == 0;
}
/**
* This will cause the spawned process to pipe it's output to a String, so it can be retrieved.
*/
public
ShellExecutor() {
byteArrayOutputStream = new ByteArrayOutputStream(8196);
PrintStream outputStream = new PrintStream(byteArrayOutputStream);
this.inputStream = null;
this.outputStream = outputStream;
this.outputErrorStream = outputStream;
}
public
ShellExecutor(final PrintStream out) {
this.inputStream = null;
this.outputStream = out;
this.outputErrorStream = out;
}
public
ShellExecutor(final InputStream in, final PrintStream out) {
this.inputStream = in;
this.outputStream = out;
this.outputErrorStream = out;
}
public
ShellExecutor(final InputStream in, final PrintStream out, final PrintStream err) {
this.inputStream = in;
this.outputStream = out;
this.outputErrorStream = err;
}
/**
* Creates extra reader/writer threads for the sub-process. This is useful depending on how the sub-process is designed to run.
*
* For a process you want interactive IO with, this is required.
*
* For a long-running sub-process, with no interactive IO, this is what you'd want.
*
* For a run-and-get-the-results process, this isn't recommended.
*
*/
public final
ShellExecutor createReadWriterThreads() {
createReadWriterThreads = true;
return this;
}
/**
* When launched from eclipse, the working directory is USUALLY the root of the project folder
*/
public final
ShellExecutor setWorkingDirectory(final String workingDirectory) {
// MUST be absolute path!!
this.workingDirectory = new File(workingDirectory).getAbsolutePath();
return this;
}
/**
* The Shell's execution environment variables. Set to `null` to only use the default environment variables (From what
* {@link System#getenv} returns)
*/
public final
ShellExecutor setEnvironment(final Map environment) {
this.environment = environment;
return this;
}
public final
ShellExecutor addArgument(final String argument) {
this.arguments.add(argument);
return this;
}
public final
ShellExecutor addArguments(final String... args) {
for (String path : args) {
this.arguments.add(path);
}
return this;
}
public final
ShellExecutor addArguments(final List paths) {
this.arguments.addAll(paths);
return this;
}
public final
ShellExecutor setExecutable(final String executableName) {
this.executableName = executableName;
return this;
}
public
ShellExecutor setExecutableDirectory(final String executableDirectory) {
// MUST be absolute path!!
this.executableDirectory = new File(executableDirectory).getAbsolutePath();
return this;
}
/**
* This will execute as a shell command (bash/cmd/etc) instead of as a forked process.
*/
public
ShellExecutor executeAsShellCommand() {
this.executeAsShell = true;
return this;
}
/**
* Sends all output data for this process to "null" in a cross platform method
*/
public
ShellExecutor pipeOutputToNull() throws IllegalArgumentException {
if (outputStream != null || outputErrorStream != null) {
throw new IllegalArgumentException("Cannot pipe shell command to 'null' if an output stream is specified");
}
if (isWindows) {
// >NUL on windows
pipeToNullString = ">NUL";
}
else {
// we will "pipe" it to /dev/null on *nix
pipeToNullString = ">/dev/null 2>&1";
}
return this;
}
/**
* @return the executable command issued to the shell
*/
public
String getCommand() {
StringBuilder execCommand = new StringBuilder();
Iterator iterator = fullCommand.iterator();
while (iterator.hasNext()) {
String s = iterator.next();
execCommand.append(s);
if (iterator.hasNext()) {
execCommand.append(" ");
}
}
return execCommand.toString();
}
public
int start() {
return start(true);
}
public
int start(final boolean waitForProcesses) {
fullCommand = new ArrayList();
if (executeAsShell) {
if (isWindows) {
fullCommand.add("cmd");
fullCommand.add("/c");
}
else {
if (defaultShell == null) {
String[] shells = new String[] {"/bin/bash", "/usr/bin/bash",
"/bin/pfbash", "/usr/bin/pfbash",
"/bin/csh", "/usr/bin/csh",
"/bin/pfcsh", "/usr/bin/pfcsh",
"/bin/jsh", "/usr/bin/jsh",
"/bin/ksh", "/usr/bin/ksh",
"/bin/pfksh", "/usr/bin/pfksh",
"/bin/ksh93", "/usr/bin/ksh93",
"/bin/pfksh93", "/usr/bin/pfksh93",
"/bin/pfsh", "/usr/bin/pfsh",
"/bin/tcsh", "/usr/bin/tcsh",
"/bin/pftcsh", "/usr/bin/pftcsh",
"/usr/xpg4/bin/sh", "/usr/xp4/bin/pfsh",
"/bin/zsh", "/usr/bin/zsh",
"/bin/pfzsh", "/usr/bin/pfzsh",
"/bin/sh", "/usr/bin/sh",};
for (String shell : shells) {
if (new File(shell).canExecute()) {
defaultShell = shell;
break;
}
}
}
if (defaultShell == null) {
throw new RuntimeException("Unable to determine the default shell for the linux/unix environment.");
}
// *nix
fullCommand.add(defaultShell);
fullCommand.add("-c");
}
// fullCommand.add(this.executableName); // done elsewhere!
} else {
// shell and working/exe directory are mutually exclusive
if (this.workingDirectory != null) {
if (!this.workingDirectory.endsWith(File.separator)) {
this.workingDirectory += File.separator;
}
}
if (this.executableDirectory != null) {
if (!this.executableDirectory.endsWith(File.separator)) {
this.executableDirectory += File.separator;
}
fullCommand.add(0, this.executableDirectory + this.executableName);
} else {
fullCommand.add(this.executableName);
}
}
// if we don't want output...
boolean pipeToNull = !pipeToNullString.isEmpty();
if (executeAsShell && !isWindows) {
// when a shell AND on *nix, we have to place ALL the args into a single "arg" that is passed in
final StringBuilder stringBuilder = new StringBuilder(1024);
stringBuilder.append(this.executableName).append(" ");
for (String arg : this.arguments) {
stringBuilder.append(arg).append(" ");
}
if (!arguments.isEmpty()) {
if (pipeToNull) {
stringBuilder.append(pipeToNullString);
}
else {
// delete last " "
stringBuilder.delete(stringBuilder.length() - 1, stringBuilder.length());
}
}
fullCommand.add(stringBuilder.toString());
} else {
for (String arg : this.arguments) {
if (arg.contains(" ")) {
// individual arguments MUST be in their own element in order to be processed properly
// (this is how it works on the command line!)
String[] split = arg.split(" ");
for (String s : split) {
s = s.trim();
if (!s.isEmpty()) {
fullCommand.add(s);
}
}
} else {
fullCommand.add(arg);
}
}
if (pipeToNull) {
fullCommand.add(pipeToNullString);
}
}
ProcessBuilder processBuilder = new ProcessBuilder(fullCommand);
if (this.workingDirectory != null) {
processBuilder.directory(new File(this.workingDirectory));
}
// These env variables are a copy of System.getenv()
Map environment = processBuilder.environment();
// Make sure all shell calls are LANG=en_US.UTF-8 THIS CAN BE OVERRIDDEN
if (isMacOsX) {
// Enable LANG overrides
environment.put("SOFTWARE", "");
}
// "export LANG=en_US.UTF-8"
environment.put("LANG", "C");
if (this.environment != null) {
for (Map.Entry e : this.environment.entrySet()) {
environment.put(e.getKey(), e.getValue());
}
}
// combine these so output is properly piped to null.
if (pipeToNull || this.outputErrorStream == null) {
processBuilder.redirectErrorStream(true);
}
try {
this.process = processBuilder.start();
} catch (Exception ex) {
if (outputErrorStream != null) {
this.outputErrorStream.println("There was a problem executing the program. Details:");
ex.printStackTrace(this.outputErrorStream);
} else {
System.err.println("There was a problem executing the program. Details:");
ex.printStackTrace();
}
if (this.process != null) {
try {
this.process.destroy();
this.process = null;
} catch (Exception e) {
if (outputErrorStream != null) {
this.outputErrorStream.println("Error destroying process:");
} else {
System.err.println("Error destroying process:");
}
e.printStackTrace(this.outputErrorStream);
}
}
}
if (this.process != null) {
if (this.outputErrorStream == null && this.outputStream == null) {
if (!pipeToNull) {
NullOutputStream nullOutputStream = new NullOutputStream();
// readers (read process -> write console)
// have to keep the output buffers from filling in the target process.
readFromProcess_output = new ProcessProxy("Process Reader: " + this.executableName,
this.process.getInputStream(),
nullOutputStream);
}
}
// we want to pipe our input/output from process to ourselves
else {
/*
* Proxy the System.out and System.err from the spawned process back
* to the user's window. This is important or the spawned process could block.
*/
// readers (read process -> write console)
readFromProcess_output = new ProcessProxy("Process Reader: " + this.executableName,
this.process.getInputStream(),
this.outputStream);
if (this.outputErrorStream != this.outputStream) {
readFromProcess_error = new ProcessProxy("Process Reader: " + this.executableName,
this.process.getErrorStream(),
this.outputErrorStream);
}
}
if (this.inputStream != null) {
/*
* Proxy System.in from the user's window to the spawned process
*/
// writer (read console -> write process)
writeToProcess_input = new ProcessProxy("Process Writer: " + this.executableName,
this.inputStream,
this.process.getOutputStream());
}
// the process can be killed in two ways
// If not in IDE, by this shutdown hook. (clicking the red square to terminate a process will not run it's shutdown hooks)
// Typing "exit" will always terminate the process
Thread hook = new Thread(new Runnable() {
@Override
public
void run() {
try {
// wait for the READER threads to die (meaning their streams have closed/EOF'd)
if (writeToProcess_input != null) {
// the INPUT (from stdin). It should be via the InputConsole, but if it's in eclipse,etc -- then this doesn't do anything
// We are done reading input, since our program has closed...
writeToProcess_input.close();
if (createReadWriterThreads) {
writeToProcess_input.join();
}
}
readFromProcess_output.close();
if (createReadWriterThreads) {
readFromProcess_output.join();
}
if (readFromProcess_error != null) {
readFromProcess_error.close();
if (createReadWriterThreads) {
readFromProcess_error.join();
}
}
} catch (InterruptedException e) {
Thread.currentThread()
.interrupt();
}
// forcibly terminate the process when it's streams have closed.
// this is for cleanup ONLY, not to actually do anything.
ShellExecutor.this.process.destroy();
}
});
hook.setName("ShellExecutor Shutdown Hook for " + this.executableName);
// add a shutdown hook to make sure that we properly terminate our spawned processes.
// hook is NOT set to daemon mode, because this is run during shutdown
// add a shutdown hook to make sure that we properly terminate our spawned processes.
try {
Runtime.getRuntime()
.addShutdownHook(hook);
} catch (IllegalStateException ignored) {
// can happen, safe to ignore
}
if (writeToProcess_input != null) {
if (createReadWriterThreads) {
writeToProcess_input.start();
}
else {
writeToProcess_input.run();
}
}
if (createReadWriterThreads) {
readFromProcess_output.start();
}
else {
readFromProcess_output.run();
}
if (readFromProcess_error != null) {
if (createReadWriterThreads) {
readFromProcess_error.start();
}
else {
readFromProcess_error.run();
}
}
int exitValue = 0;
if (waitForProcesses) {
try {
this.process.waitFor();
exitValue = this.process.exitValue();
hook.run();
} catch (InterruptedException e) {
Thread.currentThread()
.interrupt();
}
// remove the shutdown hook now that we've shutdown.
try {
Runtime.getRuntime().removeShutdownHook(hook);
} catch (IllegalStateException ignored) {
// can happen, safe to ignore
}
}
return exitValue;
}
// 1 means a problem
return 1;
}
/**
* There will never be a trailing newline character at the end of this output.
*
* @return A string representing the output of the process, null if the thread for this was interrupted or the output wasn't saved
*/
public
String getOutput() {
if (byteArrayOutputStream != null) {
return getOutput(byteArrayOutputStream);
}
return null;
}
/**
* Converts the baos to a string in a safe way. There will never be a trailing newline character at the end of this output. This will
* block until there is a line of input available.
*
* @return A string representing the output of the process, null if the thread for this was interrupted or the output wasn't saved
*/
public
String getOutputLineBuffered() {
if (byteArrayOutputStream != null) {
return getOutputLineBuffered(byteArrayOutputStream);
}
return null;
}
/**
* Converts the baos to a string in a safe way. There will never be a trailing newline character at the end of this output.
*
* @param byteArrayOutputStream the baos that is used in the {@link ShellExecutor#ShellExecutor(PrintStream)} (or similar
* calls)
*
* @return A string representing the output of the process, null if the thread for this was interrupted
*/
public static
String getOutput(final ByteArrayOutputStream byteArrayOutputStream) {
String s;
synchronized (byteArrayOutputStream) {
s = byteArrayOutputStream.toString();
byteArrayOutputStream.reset();
}
// remove trailing newline character(s)
int endIndex = s.lastIndexOf(LINE_SEPARATOR);
if (endIndex > -1) {
return s.substring(0, endIndex);
}
return s;
}
/**
* Converts the baos to a string in a safe way. There will never be a trailing newline character at the end of this output. This will
* block until there is a line of input available.
*
* @param byteArrayOutputStream the baos that is used in the {@link ShellExecutor#ShellExecutor(PrintStream)} (or similar
* calls)
*
* @return A string representing the output of the process, null if the thread for this was interrupted
*/
public static
String getOutputLineBuffered(final ByteArrayOutputStream byteArrayOutputStream) {
String s;
synchronized (byteArrayOutputStream) {
try {
byteArrayOutputStream.wait();
} catch (InterruptedException ignored) {
return null;
}
s = byteArrayOutputStream.toString();
byteArrayOutputStream.reset();
}
return s;
}
}