Merge Argeo Util and parts of Argeo JCR in Argeo Core.

[lgpl/argeo-commons.git] / org.argeo.core / src / org / argeo / util / DictionaryKeys.java

diff --git a/org.argeo.core/src/org/argeo/util/DictionaryKeys.java b/org.argeo.core/src/org/argeo/util/DictionaryKeys.java
new file mode 100644 (file)
index 0000000..d17c86f
--- /dev/null
+++ b/org.argeo.core/src/org/argeo/util/DictionaryKeys.java
@@ -0,0 +1,42 @@
+package org.argeo.util;
+
+import java.util.Dictionary;
+import java.util.Enumeration;
+import java.util.Iterator;
+
+/**
+ * Access the keys of a {@link String}-keyed {@link Dictionary} (common throughout
+ * the OSGi APIs) as an {@link Iterable} so that they are easily usable in
+ * for-each loops.
+ */
+class DictionaryKeys implements Iterable<String> {
+       private final Dictionary<String, ?> dictionary;
+
+       public DictionaryKeys(Dictionary<String, ?> dictionary) {
+               this.dictionary = dictionary;
+       }
+
+       @Override
+       public Iterator<String> iterator() {
+               return new KeyIterator(dictionary.keys());
+       }
+
+       private static class KeyIterator implements Iterator<String> {
+               private final Enumeration<String> keys;
+
+               KeyIterator(Enumeration<String> keys) {
+                       this.keys = keys;
+               }
+
+               @Override
+               public boolean hasNext() {
+                       return keys.hasMoreElements();
+               }
+
+               @Override
+               public String next() {
+                       return keys.nextElement();
+               }
+
+       }
+}