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Updated with new examples or comments for concatenated boolean option…

…s, multiple options, getOptionValues, option defaults, rearrangeble options, the -- option-end specifier, and long-form-only options.
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1 parent 43fdaec commit 261cbf9304169be9e9f997fe2e7df4d11b94af9f Ewan Mellor committed Apr 9, 2005
Showing with 102 additions and 20 deletions.
  1. +102 −20 src/jargs/examples/gnu/OptionTest.java
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122 src/jargs/examples/gnu/OptionTest.java
@@ -1,22 +1,66 @@
package jargs.examples.gnu;
+import java.util.Enumeration;
+import java.util.Vector;
+
import jargs.gnu.CmdLineParser;
+
public class OptionTest {
private static void printUsage() {
- System.err.println("usage: prog [{-v,--verbose}] [{-n,--name} a_name] "+
- "[{-s,--size} a_number] [{-f,--fraction} a_float] "+
- "[a_nother]");
+ System.err.println(
+"Usage: OptionTest [-d,--debug] [{-v,--verbose}] [{--alt}] [{--name} a_name]\n" +
+" [{-s,--size} a_number] [{-f,--fraction} a_float] [a_nother]");
}
public static void main( String[] args ) {
+
+ // First, you must create a CmdLineParser, and add to it the
+ // appropriate Options.
+
+ // To start with, we add the Options -d, -v, -s, and -f, with aliases
+ // --debug, --verbose, --size, and --fraction respectively.
+
+ // The -d and -v options have no associated value -- they are either
+ // present, or they are not. The -s and -f options take integer and
+ // double-precision floating-point values respectively.
+
CmdLineParser parser = new CmdLineParser();
+ CmdLineParser.Option debug = parser.addBooleanOption('d', "debug");
CmdLineParser.Option verbose = parser.addBooleanOption('v', "verbose");
CmdLineParser.Option size = parser.addIntegerOption('s', "size");
- CmdLineParser.Option name = parser.addStringOption('n', "name");
CmdLineParser.Option fraction = parser.addDoubleOption('f', "fraction");
+ // Options may have just a long form with no corresponding short form.
+ // Here, we add --alt and --name options.
+
+ CmdLineParser.Option alt = parser.addBooleanOption("alt");
+ CmdLineParser.Option name = parser.addStringOption("name");
+
+
+ // Next, you must parse the user-provided command line arguments, and
+ // catch any errors therein.
+
+ // Options may appear on the command line in any order, and may even
+ // appear after some or all of the non-option arguments.
+
+ // If the user needs to specify non-option arguments that start with a
+ // minus, then they may indicate the end of the parsable options with
+ // -- , like this:
+
+ // prog -f 20 -- -10 -fred
+
+ // The -f 20 will be parsed as the fraction option, with the value 20.
+ // The -10 and -fred arguments will be regarded as non-option
+ // arguments, and passed through getRemainingArgs as unparsed Strings.
+
+ // Short boolean options may be specified separately (-d -v) or
+ // together (-dv).
+
+ // Options with values may be given on the command line as -f 1.0 or
+ // --fraction=1.0.
+
try {
parser.parse(args);
}
@@ -26,32 +70,70 @@ public static void main( String[] args ) {
System.exit(2);
}
- // Extract the values entered for the various options -- if the
- // options were not specified, the corresponding values will be
- // null.
- Boolean verboseValue = (Boolean)parser.getOptionValue(verbose);
- Integer sizeValue = (Integer)parser.getOptionValue(size);
+
+ // For options that may be specified only zero or one time, the value
+ // of that option may be extracted as shown below. If the options
+ // were not specified, the corresponding values will be null.
+
+ Boolean debugValue = (Boolean)parser.getOptionValue(debug);
String nameValue = (String)parser.getOptionValue(name);
- Double fractionValue = (Double)parser.getOptionValue(fraction);
- // For testing purposes, we just print out the option values
- System.out.println("verbose: " + verboseValue);
+ // Alternatively, you may specify a default value. This will be
+ // returned (instead of null) when the command line argument is
+ // missing.
+
+ Boolean altValue =
+ (Boolean)parser.getOptionValue(alt, Boolean.FALSE);
+ Integer sizeValue =
+ (Integer)parser.getOptionValue(size, new Integer(42));
+
+ // If your application requires it, options may be specified more than
+ // once. In this case, you may get all the values specified by the
+ // user, as a Vector:
+
+ Vector fractionValues = parser.getOptionValues(fraction);
+
+ // Alternatively, you may make the loop explicit:
+
+ int verbosity = 0;
+ while (true) {
+ Boolean verboseValue = (Boolean)parser.getOptionValue(verbose);
+
+ if (verboseValue == null) {
+ break;
+ }
+ else {
+ verbosity++;
+ }
+ }
+
+ // The remaining command-line arguments -- those that do not start
+ // with a minus sign -- can be captured like this:
+
+ String[] otherArgs = parser.getRemainingArgs();
+
+
+ // For testing purposes, we just print out the option values and
+ // remaining command-line arguments. In a real program, of course,
+ // one would pass them to a function that does something more useful.
+
+ System.out.println("debug: " + debugValue);
+ System.out.println("alt: " + altValue);
System.out.println("size: " + sizeValue);
System.out.println("name: " + nameValue);
- System.out.println("fraction: " + fractionValue);
- // Extract the trailing command-line arguments ('a_nother') in the
- // usage string above.
- String[] otherArgs = parser.getRemainingArgs();
+ System.out.println("verbosity: " + verbosity);
+
+ Enumeration e = fractionValues.elements();
+ while (e.hasMoreElements()) {
+ System.out.println("fraction: " + (Double)e.nextElement());
+ }
+
System.out.println("remaining args: ");
for ( int i = 0; i < otherArgs.length; ++i ) {
System.out.println(otherArgs[i]);
}
- // In a real program, one would pass the option values and other
- // arguments to a function that does something more useful.
-
System.exit(0);
}
-
}

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