org.apache.juneau.utils.ProcBuilder Maven / Gradle / Ivy
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package org.apache.juneau.utils;
import static org.apache.juneau.internal.IOUtils.*;
import static org.apache.juneau.internal.StringUtils.*;
import java.io.*;
import java.lang.reflect.*;
import java.util.*;
import java.util.logging.*;
import org.apache.juneau.internal.*;
import org.apache.juneau.utils.IOPipe.*;
/**
* Utility class for running operating system processes.
*
*
* Similar to {@link java.lang.ProcessBuilder} but with additional features.
*/
public class ProcBuilder {
private java.lang.ProcessBuilder pb = new java.lang.ProcessBuilder();
private TeeWriter outWriters = new TeeWriter(), logWriters = new TeeWriter();
private LineProcessor lp;
private Process p;
private int maxExitStatus = 0;
private boolean byLines;
private String divider = "--------------------------------------------------------------------------------";
/**
* Creates a process builder with the specified arguments.
*
*
* Equivalent to calling ProcessBuilder.create().command(args);
*
* @param args The command-line arguments.
* @return A new process builder.
*/
public static ProcBuilder create(Object...args) {
return new ProcBuilder().command(args);
}
/**
* Creates an empty process builder.
*
* @return A new process builder.
*/
public static ProcBuilder create() {
return new ProcBuilder().command();
}
/**
* Command arguments.
*
*
* Arguments can be collections or arrays and will be automatically expanded.
*
* @param args The command-line arguments.
* @return This object (for method chaining).
*/
public ProcBuilder command(Object...args) {
return commandIf(ANY, args);
}
/**
* Command arguments if the specified matcher matches.
*
*
* Can be used for specifying OS-specific commands.
*
*
Example:
*
* ProcBuilder pb = ProcBuilder
* .create()
* .commandIf(WINDOWS , "cmd /c dir" )
* .commandIf(UNIX , "bash -c ls" )
* .merge()
* .execute();
*
*
* @param m The matcher.
* @param args The command line arguments if matcher matches.
* @return This object (for method chaining).
*/
public ProcBuilder commandIf(Matcher m, Object...args) {
if (m.matches())
pb.command(toList(args));
return this;
}
/**
* Append to the command arguments.
*
*
* Arguments can be collections or arrays and will be automatically expanded.
*
* @param args The command-line arguments.
* @return This object (for method chaining).
*/
public ProcBuilder append(Object...args) {
return appendIf(ANY, args);
}
/**
* Append to the command arguments if the specified matcher matches.
*
*
* Arguments can be collections or arrays and will be automatically expanded.
*
* @param m The matcher.
* @param args The command line arguments if matcher matches.
* @return This object (for method chaining).
*/
public ProcBuilder appendIf(Matcher m, Object...args) {
if (m.matches())
pb.command().addAll(toList(args));
return this;
}
/**
* Merge STDOUT and STDERR into a single stream.
*
* @return This object (for method chaining).
*/
public ProcBuilder merge() {
pb.redirectErrorStream(true);
return this;
}
/**
* Use by-lines mode.
*
*
* Flushes output after every line of input.
*
* @return This object (for method chaining).
*/
public ProcBuilder byLines() {
this.byLines = true;
return this;
}
/**
* Pipe output to the specified writer.
*
*
* The method can be called multiple times to write to multiple writers.
*
* @param w The writer to pipe to.
* @param close Close the writer afterwards.
* @return This object (for method chaining).
*/
public ProcBuilder pipeTo(Writer w, boolean close) {
this.outWriters.add(w, close);
return this;
}
/**
* Pipe output to the specified writer, but don't close the writer.
*
* @param w The writer to pipe to.
* @return This object (for method chaining).
*/
public ProcBuilder pipeTo(Writer w) {
return pipeTo(w, false);
}
/**
* Pipe output to the specified writer, including the command and return code.
*
*
* The method can be called multiple times to write to multiple writers.
*
* @param w The writer to pipe to.
* @param close Close the writer afterwards.
* @return This object (for method chaining).
*/
public ProcBuilder logTo(Writer w, boolean close) {
this.logWriters.add(w, close);
this.outWriters.add(w, close);
return this;
}
/**
* Pipe output to the specified writer, including the command and return code.
*
*
* The method can be called multiple times to write to multiple writers.
* Don't close the writer afterwards.
*
* @param w The writer to pipe to.
* @return This object (for method chaining).
*/
public ProcBuilder logTo(Writer w) {
return logTo(w, false);
}
/**
* Pipe output to the specified writer, including the command and return code.
* The method can be called multiple times to write to multiple writers.
*
* @param level The log level.
* @param logger The logger to log to.
* @return This object (for method chaining).
*/
public ProcBuilder logTo(final Level level, final Logger logger) {
if (logger.isLoggable(level)) {
logTo(new StringWriter() {
private boolean isClosed; // Prevents messages from being written twice.
@Override /* Writer */
public void close() {
if (! isClosed)
logger.log(level, this.toString());
isClosed = true;
}
}, true);
}
return this;
}
/**
* Line processor to use to process/convert lines of output returned by the process.
*
* @param lp The new line processor.
* @return This object (for method chaining).
*/
public ProcBuilder lp(LineProcessor lp) {
this.lp = lp;
return this;
}
/**
* Append the specified environment variables to the process.
*
* @param env The new set of environment variables.
* @return This object (for method chaining).
*/
@SuppressWarnings({"rawtypes"})
public ProcBuilder env(Map env) {
if (env != null)
for (Map.Entry e : (Set)env.entrySet())
environment(e.getKey().toString(), e.getValue() == null ? null : e.getValue().toString());
return this;
}
/**
* Append the specified environment variable.
*
* @param key The environment variable name.
* @param val The environment variable value.
* @return This object (for method chaining).
*/
public ProcBuilder environment(String key, String val) {
pb.environment().put(key, val);
return this;
}
/**
* Sets the directory where the command will be executed.
*
* @param directory The directory.
* @return This object (for method chaining).
*/
public ProcBuilder directory(File directory) {
pb.directory(directory);
return this;
}
/**
* Sets the maximum allowed return code on the process call.
*
*
* If the return code exceeds this value, an IOException is returned on the {@link #run()} command.
* The default value is '0'.
*
* @param maxExitStatus The maximum exit status.
* @return This object (for method chaining).
*/
public ProcBuilder maxExitStatus(int maxExitStatus) {
this.maxExitStatus = maxExitStatus;
return this;
}
/**
* Run this command and pipes the output to the specified writer or output stream.
*
* @return The exit code from the process.
* @throws IOException
* @throws InterruptedException
*/
public int run() throws IOException, InterruptedException {
if (pb.command().size() == 0)
throw new IOException("No command specified in ProcBuilder.");
try {
logWriters.append(divider).append('\n').flush();
logWriters.append(join(pb.command(), " ")).append('\n').flush();
p = pb.start();
IOPipe.create(p.getInputStream(), outWriters).lineProcessor(lp).byLines(byLines).run();
int rc = p.waitFor();
logWriters.append("Exit: ").append(String.valueOf(p.exitValue())).append('\n').flush();
if (rc > maxExitStatus)
throw new IOException("Return code "+rc+" from command " + join(pb.command(), " "));
return rc;
} finally {
close();
}
}
/**
* Run this command and returns the output as a simple string.
*
* @return The output from the command.
* @throws IOException
* @throws InterruptedException
*/
public String getOutput() throws IOException, InterruptedException {
StringWriter sw = new StringWriter();
pipeTo(sw).run();
return sw.toString();
}
/**
* Returns the output from this process as a {@link Scanner}.
*
* @return The output from the process as a Scanner object.
* @throws IOException
* @throws InterruptedException
*/
public Scanner getScanner() throws IOException, InterruptedException {
StringWriter sw = new StringWriter();
pipeTo(sw, true);
run();
return new Scanner(sw.toString());
}
/**
* Destroys the underlying process.
*
*
* This method is only needed if the {@link #getScanner()} method was used.
*/
private void close() {
closeQuietly(logWriters, outWriters);
if (p != null)
p.destroy();
}
/**
* Specifies interface for defining OS-specific commands.
*/
public abstract static class Matcher {
abstract boolean matches();
}
static final String OS = System.getProperty("os.name").toLowerCase();
/** Operating system matcher: Any operating system. */
public static final Matcher ANY = new Matcher() {
@Override boolean matches() {
return true;
}
};
/** Operating system matcher: Any Windows system. */
public static final Matcher WINDOWS = new Matcher() {
@Override boolean matches() {
return OS.indexOf("win") >= 0;
}
};
/** Operating system matcher: Any Mac system. */
public static final Matcher MAC = new Matcher() {
@Override boolean matches() {
return OS.indexOf("mac") >= 0;
}
};
/** Operating system matcher: Any Unix or Linux system. */
public static final Matcher UNIX = new Matcher() {
@Override boolean matches() {
return OS.indexOf("nix") >= 0 || OS.indexOf("nux") >= 0 || OS.indexOf("aix") > 0;
}
};
private static List toList(Object...args) {
List l = new LinkedList<>();
for (Object o : args) {
if (o.getClass().isArray())
for (int i = 0; i < Array.getLength(o); i++)
l.add(Array.get(o, i).toString());
else if (o instanceof Collection)
for (Object o2 : (Collection>)o)
l.add(o2.toString());
else
l.add(o.toString());
}
return l;
}
}