CommandLineUtils.java

package edu.berkeley.nlp.util;

import java.util.HashMap;
import java.util.Map;

/**
 * Utilities for managing command line flags and arguments.
 *
 * @author Dan Klein
 */
public class CommandLineUtils {
  /**
   * Simple method which turns an array of command line arguments into a map,
   * where each token starting with a '-' is a key and the following non '-'
   * initial token, if there is one, is the value.  For example, '-size 5
   * -verbose' will produce keys (-size,5) and (-verbose,null).
   */
  public static Map<String, String> simpleCommandLineParser(String[] args) {
    Map<String, String> map = new HashMap<String, String>();
    for (int i = 0; i <= args.length; i++) {
      String key = (i > 0 ? args[i - 1] : null);
      String value = (i < args.length ? args[i] : null);//.toLowerCase();
      if (key == null || key.startsWith("-")) {
        if (value != null && value.startsWith("-"))
          value = null;
        if (key != null || value != null)
          map.put(key, value);
        
      }
    }
    return map;
  }

  /**
   * Simple method to look up a key in an argument map.  Returns the
   * defaultValue if the argument is not specified in the map.
   */
  public static String getValueOrUseDefault(Map<String, String> args, String key, String defaultValue) {
    if (args.containsKey(key))
      return args.get(key);
    return defaultValue;
  }
}