1 files changed, 42 insertions, 0 deletions
diff --git a/args4j/args4j-tools/src/org/kohsuke/args4j/apt/AnnotationVisitorReorderer.java b/args4j/args4j-tools/src/org/kohsuke/args4j/apt/AnnotationVisitorReorderer.java
new file mode 100644
index 0000000..735a2cd
--- /dev/null
+++ b/args4j/args4j-tools/src/org/kohsuke/args4j/apt/AnnotationVisitorReorderer.java
@@ -0,0 +1,42 @@
+package org.kohsuke.args4j.apt;
+
+import java.util.*;
+
+/**
+ * Reorders the annotation according to their canonical name
+ */
+public class AnnotationVisitorReorderer implements AnnotationVisitor {
+    private AnnotationVisitor target;
+
+    private List<OptionWithUsage> arguments = new ArrayList<OptionWithUsage>();
+
+    public AnnotationVisitorReorderer(AnnotationVisitor target) {
+        this.target = target;
+    }
+
+    public void onOption(String name, String usage) {
+        throw new UnsupportedOperationException("method not used");
+    }
+
+    public void onOption(OptionWithUsage optionWithUsage) {
+        arguments.add(optionWithUsage);
+    }
+
+    public void done() {
+        reorderArguments();
+        for (OptionWithUsage argument : arguments) {
+            target.onOption(argument);
+        }
+        target.done();
+    }
+
+    private void reorderArguments() {
+        Collections.sort(arguments, new NaturalOrderOptionsComparator());
+    }
+
+    private static class NaturalOrderOptionsComparator implements Comparator<OptionWithUsage> {
+        public int compare(OptionWithUsage o1, OptionWithUsage o2) {
+            return o1.option.name().compareTo(o2.option.name());
+        }
+    }
+}