pollev / shell_command_executor_lib

A Java Lib designed to make executing shell commands easier and safer

Shell Command Execution Library

This is a Java library that intends to make it easier and safer to execute shell commands on the operating system using Runtime.exec(). Note: It is probably advised to just use java's ProcessBuilder but this is a fun project to work on.

Installation

1. Clone repository
2. run mvn install
3. Grab Shell-Command-Executor-Lib-?.?.?-SNAPSHOT.jar from the target folder
4. Add the jar to your project. (Using maven/eclipse/manually)

Usage

To use this library simply make a subclass of the abstract "Command" class. This will force you to overwrite 2 methods that implement your custom command. The abstract Command superclass provides convenient methods for analyzing the result of the process.

After creating the command object you can execute it using:

CommandExecutor exec = CommandExecutor.getCommandExecutor();
Command customCommand = new YourCommand();
exec.executeCommand(customCommand);

A very simple example custom Command class:

public class ExampleCommand extends Command{

  @Override
  public String getCommand() {
    return "ls";
  }

  @Override
  public OS getOSType() {
	  return OS.UNIX;
  }
}

A slightly more advanced custom Command class:

public class DirectoryListCommand extends Command{

	private final String command;
	private final OS osType;


	public DirectoryListCommand() {
		this.osType = CommandExecutor.getCommandExecutor().getOSType();
		
		if(this.osType == OS.UNIX){
			this.command = "ls";
		}else if(this.osType == OS.WINDOWS){
			this.command = "dir";
		}else{
			// Hoping echo at least exists, in real scenario, throw exception if required
			this.command = "echo OS type not supported";
		}
	}
	
	@Override
	public String getCommand() {
		return this.command;
	}

	@Override
	public OS getOSType() {
		return this.osType;
	}

}