abstractcommand.java

一个自然语言处理的Java开源工具包。LingPipe目前已有很丰富的功能

/*
 * LingPipe v. 3.5
 * Copyright (C) 2003-2008 Alias-i
 *
 * This program is licensed under the Alias-i Royalty Free License
 * Version 1 WITHOUT ANY WARRANTY, without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the Alias-i
 * Royalty Free License Version 1 for more details.
 *
 * You should have received a copy of the Alias-i Royalty Free License
 * Version 1 along with this program; if not, visit
 * http://alias-i.com/lingpipe/licenses/lingpipe-license-1.txt or contact
 * Alias-i, Inc. at 181 North 11th Street, Suite 401, Brooklyn, NY 11211,
 * [phone].
 */

package com.aliasi.util;

import java.io.File;

import java.util.Properties;

/**
 * A <code>CommandLineArguments</code> object represents a the
 * command-line arguments.  It is constructed with an array of
 * command-line arguments and an optional properties value specifying
 * default values.
 *
 * <p> Arguments of the form
 * <code>-<i>Property</i>=<i>Value</i></code> induce the property
 * value pair specified.  Argument values may be empty, in which
 * case the value will be the empty string.

 * <p>Arguments of the form <code>-<i>Flag</i></code> not matching the
 * previous form induce properties <code><i>Flag</i>=yes</code>.  Bare
 * arguments with of the form <code><i>BareArgument</i></code> induce
 * properties <code>BARE_ARG_<i>i</i>=<i>BareArgument</i></code> so
 * that bare arguments may be retrieved by position; bare arguments
 * equal to the empty string are ignored.</p>
 *
 * <P>Because commands are based on the {@link #run()} method, they
 * have been defined to implement the {@link Runnable} interface.
 *
 * @author  Bob Carpenter
 * @version 3.6
 * @since   LingPipe1.0
 */
public abstract class AbstractCommand implements Runnable {

    private final long mStartTime;

    private final Properties mProperties;

    /**
     * Counter for bare arguments.
     */
    private int mBareArgCount = 0;

    /**
     * The default properties values for this command.
     */
    private Properties mDefaultProperties = null;

    /**
     * Constructs a command-line arguments object from the specified
     * arguments list using no default values.
     *
     * @param args Command-line arguments.
     * @throws IllegalArgumentException If the arguments are not well
     * formed.
     */
    public AbstractCommand(String[] args) {
        this(args,new Properties());
    }

    /**
     * Constructs a command-line arguments object from the specified
     * arguments using the specified properties as default values.
     *
     * @param args Command-line arguments.
     * @param defaultProperties Default values for properties.
     * @throws IllegalArgumentException If the arguments are not well
     * formed.
     */
    public AbstractCommand(String[] args,
                           Properties defaultProperties) {
        mDefaultProperties = defaultProperties;
        mProperties = new Properties(defaultProperties);
        parse(args);
        mStartTime = System.currentTimeMillis();
    }

    /**
     * Adds the specified key and value as default arguments.
     *
     * @param property Name of property.
     * @param defaultValue Default value for property.
     */
    public void addDefaultProperty(String property, String defaultValue) {
        mDefaultProperties.setProperty(property,defaultValue);
    }


    /**
     * Return the elapsed time since the construction of
     * this command in milliseconds.
     *
     * @return The elapsed time since the construction of
     * this command in milliseconds.
     */
    public long elapsedTimeMillis() {
        return System.currentTimeMillis() - mStartTime;
    }

    /**
     * Return the time at which this command was constructed.
     *
     * @return The time at which this command was constructed.
     */
    public long startTimeMillis() {
        return mStartTime;
    }


    /**
     * Runs the abstract command.
     */
    public abstract void run();

    /**
     * Returns the number of bare arguments supplied on the command
     * line.
     *
     * @return Number of bare arguments supplied on the command line.
     */
    public int numBareArguments() {
        return mBareArgCount;
    }

    /**
     * Returns the array of bare arguments, in order, supplied on the
     * command line.  Bare arguments are arguments that do not begin
     * with a minus sign (<code>-</code>) indicating a flag or
     * property.
     *
     * @return The array of bare arguments.
     */
    public String[] bareArguments() {
    String[] arguments = new String[numBareArguments()];
    for (int i = 0; i < arguments.length; ++i)
        arguments[i] = getBareArgument(i);
    return arguments;
    }

    /**
     * Returns <code>true</code> if the arguments set the specified
     * flag.  Note that this method returns <code>false</code> for
     * properties; see {@link #hasProperty(String)}.
     *
     * @param arg The argument to test for existence on the command line.
     * @return <code>true</code> if the argument was specified on the
     * command line preceded by a <code>'-'</code>.
     */
    public boolean hasFlag(String arg) {
        String value = mProperties.getProperty(arg);
        return value != null
            && value.equals(HAS_PROPERTY_VALUE);
    }

    /**
     * Returns <code>true</code> if the arguments have the
     * specified property defined.  Note that this method
     * returns false for flags; see {@link #hasFlag(String)}.
     */
    public boolean hasProperty(String arg) {
        String value = mProperties.getProperty(arg);
        return value != null
            && !value.equals(HAS_PROPERTY_VALUE);
    }

    /**
     * Returns the specified bare argument.
     *
     * @param n Index of bare argument to return.
     * @return Value of bare argument in specified position, or
     * <code>null</code> if not specified.
     */
    public String getBareArgument(int n) {
        return mProperties.getProperty(bareArgumentProperty(n));
    }

    /**
     * Returns the value of the command-line argument with the
     * specified key, or the value of the key in the default
     * properties, or <code>null</code> if it does not exist.  The
     * property exists in the command-line if it was specified by
     * <code>"-<i>Arg</i>=<i>Value</i></code>.
     *
     * @param key Name of command-line argument to return.
     * @return Value of command-line argument.
     */
    public String getArgument(String key) {
        return mProperties.getProperty(key);
    }

    /**
     * Returns the complete list of command-line parameters for this
     * abstract command.  The returned result encapsulates all of the
     * argument parameters and default parameters with values.  
     *
     * <p>Flags are included as properties with the flag as key and
     * value {@link #HAS_PROPERTY_VALUE}.  Bare arguments are included
     * with prefixes consisting of {@link #BARE_ARG_PREFIX} followed
     * by a number.
     *
     * @return The properties representing the arguments.
     */
    public Properties getArguments() {
    return mProperties;
    }

    /**
     * Returns the same value as {@link #getArgument(String)}, but
     * throws an exception if the argument does not exist.
     *
     * @param key Name of command-line argument to return.
     * @return Value of command-line argument.
     * @throws IllegalArgumentException If there is no value specified
     * for the given key.
     */
    public String getExistingArgument(String key)
        throws IllegalArgumentException{

        String result = mProperties.getProperty(key);
        if (result == null)
            illegalPropertyArgument("Require value.",
                                    key);
        return result;
    }

    /**
     * Return the array of string values specified by the
     * value of the specified key as a comma-separated values list,
     * as defined in {@link Arrays#csvToArray(String)}.
     *
     * @param key Name of command-line argument to parse as
     * comma-separated values.
     * @return Array of values specified by key's value.
     * @throws IllegalArgumentException If the specified key is not
     * defined.
     */
    public String[] getCSV(String key) {
        String csv = getExistingArgument(key);
        return Arrays.csvToArray(csv);
    }


    /**
     * Returns <code>true</code> if there is a command-line
     * argument specified for the key.
     *
     * @return <code>true</code> if there is a command-line argument
     * specified for the key.
     */
    public boolean hasArgument(String key) {
        return mProperties.containsKey(key);
    }

    /**
     * Returns the value of the argument with the specified key
     * converted to an integer value.
     *
     * @param key Name of argument to convert to an integer and
     * return.
     * @return Integer value of specified command-line argument.
     * @throws IllegalArgumentException If there is a number format
     * exception converting the argument to an integer, or if there is
     * no value supplied.
     */
    public int getArgumentInt(String key) {
        String valString = getExistingArgument(key);
        try {
            return Integer.parseInt(valString);
        } catch (NumberFormatException e) {
            illegalPropertyArgument("Required integer.", key);
        // required for compiler; doen't know catch always throws
        return -1;
        }
    }

    /**
     * Returns the value of the argument with the specified key
     * converted to a long value.
     *
     * @param key Name of argument to convert to a long and
     * return.
     * @return Long value of specified command-line argument.
     * @throws IllegalArgumentException If there is a number format
     * exception converting the argument to an integer, or if there is
     * no value supplied.
     */