/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.cli;
/**
* <p>
* Allows Options to be created from a single String.
* The pattern contains various single character flags and via
* an optional punctuation character, their expected type.
* </p>
*
* <table border="1">
* <tr><td>a</td><td>-a flag</td></tr>
* <tr><td>b@</td><td>-b [classname]</td></tr>
* <tr><td>c></td><td>-c [filename]</td></tr>
* <tr><td>d+</td><td>-d [classname] (creates object via empty contructor)</td></tr>
* <tr><td>e%</td><td>-e [number] (creates Double/Long instance depeding on existing of a '.')</td></tr>
* <tr><td>f/</td><td>-f [url]</td></tr>
* <tr><td>g:</td><td>-g [string]</td></tr>
* </table>
*
* <p>
* For example, the following allows command line flags of '-v -p string-value -f /dir/file'.
* </p>
* <code>Options options = PatternOptionBuilder.parsePattern("vp:f/");</code>
*
* <p>
* TODO These need to break out to OptionType and also
* to be pluggable.
* </p>
*
* @author Henri Yandell (bayard @ generationjava.com)
* @version $Revision: 542144 $
*/
public class PatternOptionBuilder {
/** String class */
public static final Class STRING_VALUE = java.lang.String.class;
/** Object class */
public static final Class OBJECT_VALUE = java.lang.Object.class;
/** Number class */
public static final Class NUMBER_VALUE = java.lang.Number.class;
/** Date class */
public static final Class DATE_VALUE = java.util.Date.class;
/** Class class */
public static final Class CLASS_VALUE = java.lang.Class.class;
/// can we do this one??
// is meant to check that the file exists, else it errors.
// ie) it's for reading not writing.
/** FileInputStream class */
public static final Class EXISTING_FILE_VALUE =
java.io.FileInputStream.class;
/** File class */
public static final Class FILE_VALUE = java.io.File.class;
/** File array class */
public static final Class FILES_VALUE = java.io.File[].class;
/** URL class */
public static final Class URL_VALUE = java.net.URL.class;
/**
* <p>Retrieve the class that <code>ch</code> represents.</p>
*
* @param ch the specified character
* @return The class that <code>ch</code> represents
*/
public static Object getValueClass(char ch)
{
if (ch == '@')
{
return PatternOptionBuilder.OBJECT_VALUE;
}
else if (ch == ':')
{
return PatternOptionBuilder.STRING_VALUE;
}
else if (ch == '%')
{
return PatternOptionBuilder.NUMBER_VALUE;
}
else if (ch == '+')
{
return PatternOptionBuilder.CLASS_VALUE;
}
else if (ch == '#')
{
return PatternOptionBuilder.DATE_VALUE;
}
else if (ch == '<')
{
return PatternOptionBuilder.EXISTING_FILE_VALUE;
}
else if (ch == '>')
{
return PatternOptionBuilder.FILE_VALUE;
}
else if (ch == '*')
{
return PatternOptionBuilder.FILES_VALUE;
}
else if (ch == '/')
{
return PatternOptionBuilder.URL_VALUE;
}
return null;
}
/**
* <p>Returns whether <code>ch</code> is a value code, i.e.
* whether it represents a class in a pattern.</p>
*
* @param ch the specified character
* @return true if <code>ch</code> is a value code, otherwise false.
*/
public static boolean isValueCode(char ch)
{
if ((ch != '@') && (ch != ':') && (ch != '%') && (ch != '+')
&& (ch != '#') && (ch != '<') && (ch != '>') && (ch != '*')
&& (ch != '/') && (ch != '!'))
{
return false;
}
return true;
}
/**
* <p>Returns the {@link Options} instance represented by
* <code>pattern</code>.</p>
*
* @param pattern the pattern string
* @return The {@link Options} instance
*/
public static Options parsePattern(String pattern)
{
int sz = pattern.length();
char opt = ' ';
char ch = ' ';
boolean required = false;
Object type = null;
Options options = new Options();
for (int i = 0; i < sz; i++)
{
ch = pattern.charAt(i);
// a value code comes after an option and specifies
// details about it
if (!isValueCode(ch))
{
if (opt != ' ')
{
OptionBuilder.hasArg(type != null);
OptionBuilder.isRequired(required);
OptionBuilder.withType(type);
// we have a previous one to deal with
options.addOption(OptionBuilder.create(opt));
required = false;
type = null;
opt = ' ';
}
opt = ch;
}
else if (ch == '!')
{
required = true;
}
else
{
type = getValueClass(ch);
}
}
if (opt != ' ')
{
OptionBuilder.hasArg(type != null);
OptionBuilder.isRequired(required);
OptionBuilder.withType(type);
// we have a final one to deal with
options.addOption(OptionBuilder.create(opt));
}
return options;
}
}