Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
//License from project: Open Source License 

import java.io.IOException;

import java.io.StringReader;

import java.util.List;
import java.util.Vector;

public class Main {
    /**
     * Takes a single line command as a string and breaks it up in tokens
     * acceptable for the java.lang.ProcessBuilder.ProcessBuilder
     * @param command Complete command as a single string
     * @return Array of strings that are acceptable tokens for ProcessBuilder
     * @throws Exception 
     */
    static public List<String> breakUpCommand(String command) throws Exception {
        try {
            List<String> commandTokens = new Vector<String>();

            StringBuilder currentToken = null;
            boolean isTokenQuoted = false;
            StringReader sr = new StringReader(command);
            int b = sr.read();
            while (b >= 0) {
                char c = (char) b;

                if (null == currentToken) {
                    // At token is not in progress

                    // Skipping spaces
                    if (' ' == c || '\t' == c) {

                    } else if ('"' == c) {
                        // Starting a quoted token
                        currentToken = new StringBuilder();
                        //currentToken.append(c);
                        isTokenQuoted = true;
                    } else {
                        // Starting a non-quoted token
                        currentToken = new StringBuilder();
                        currentToken.append(c);
                        isTokenQuoted = false;
                    }

                } else if (isTokenQuoted) {
                    // A quoted token is in progress. It ends with a quote
                    if ('"' == c) {
                        //currentToken.append(c);
                        String token = currentToken.toString();
                        currentToken = null;
                        commandTokens.add(token);

                    } else {
                        // Continuation
                        currentToken.append(c);
                    }

                } else {
                    // A non-quoted token is in progress. It ends with a space
                    if (' ' == c || '\t' == c) {
                        String token = currentToken.toString();
                        currentToken = null;
                        commandTokens.add(token);

                    } else {
                        // Continuation
                        currentToken.append(c);
                    }
                }

                b = sr.read();
            }

            if (null != currentToken) {
                String token = currentToken.toString();
                commandTokens.add(token);
            }

            return commandTokens;

        } catch (IOException e) {
            throw new Exception("Error while breaking up command into tokens: " + command, e);
        }
    }
}