/*
* Copyright 2002-2011 the original author or authors.
*
* Licensed 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.springframework.core.env;
/**
* Parses a {@code String[]} of command line arguments in order to populate a
* {@link CommandLineArgs} object.
*
* <h3>Working with option arguments</h3>
* Option arguments must adhere to the exact syntax:
* <pre class="code">--optName[=optValue]</pre>
* That is, options must be prefixed with "{@code --}", and may or may not specify a value.
* If a value is specified, the name and value must be separated <em>without spaces</em>
* by an equals sign ("=").
*
* <h4>Valid examples of option arguments</h4>
* <pre class="code">
* --foo
* --foo=bar
* --foo="bar then baz"
* --foo=bar,baz,biz</pre>
*
* <h4>Invalid examples of option arguments</h4>
* <pre class="code">
* -foo
* --foo bar
* --foo = bar
* --foo=bar --foo=baz --foo=biz</pre>
*
* <h3>Working with non-option arguments</h3>
* Any and all arguments specified at the command line without the "{@code --}" option
* prefix will be considered as "non-option arguments" and made available through the
* {@link CommandLineArgs#getNonOptionArgs()} method.
*
* @author Chris Beams
* @since 3.1
*/
class SimpleCommandLineArgsParser {
/**
* Parse the given {@code String} array based on the rules described {@linkplain
* SimpleCommandLineArgsParser above}, returning a fully-populated
* {@link CommandLineArgs} object.
* @param args command line arguments, typically from a {@code main()} method
*/
public CommandLineArgs parse(String... args) {
CommandLineArgs commandLineArgs = new CommandLineArgs();
for (String arg : args) {
if (arg.startsWith("--")) {
String optionText = arg.substring(2, arg.length());
String optionName;
String optionValue = null;
if (optionText.contains("=")) {
optionName = optionText.substring(0, optionText.indexOf("="));
optionValue = optionText.substring(optionText.indexOf("=")+1, optionText.length());
}
else {
optionName = optionText;
}
if (optionName.isEmpty() || (optionValue != null && optionValue.isEmpty())) {
throw new IllegalArgumentException("Invalid argument syntax: " + arg);
}
commandLineArgs.addOptionArg(optionName, optionValue);
}
else {
commandLineArgs.addNonOptionArg(arg);
}
}
return commandLineArgs;
}
}