X-Git-Url: https://git.argeo.org/?a=blobdiff_plain;f=org.argeo.util%2Fsrc%2Forg%2Fargeo%2Futil%2FLangUtils.java;h=1aee28c03c776d7438cc266e4842dee7e21af671;hb=3c1cdc594d954520b14646102b366290bdad58c7;hp=36bec240e83601aedd915a342f377b5aef89b1d4;hpb=74595e8270dcca6c4f9cfbded8e37d7b4300b2bd;p=lgpl%2Fargeo-commons.git

diff --git a/org.argeo.util/src/org/argeo/util/LangUtils.java b/org.argeo.util/src/org/argeo/util/LangUtils.java
index 36bec240e..1aee28c03 100644
--- a/org.argeo.util/src/org/argeo/util/LangUtils.java
+++ b/org.argeo.util/src/org/argeo/util/LangUtils.java
@@ -11,11 +11,12 @@ import java.time.ZonedDateTime;
 import java.time.temporal.ChronoUnit;
 import java.time.temporal.Temporal;
 import java.util.ArrayList;
-import java.util.Collections;
+import java.util.Collection;
 import java.util.Dictionary;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.Hashtable;
+import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.Properties;
@@ -93,6 +94,20 @@ public class LangUtils {
 		return res;
 	}
 
+	/** Converts a {@link Dictionary} to a {@link Map}. */
+	public static Map<String, Object> dictToMap(Dictionary<String, ?> properties) {
+		if (properties == null) {
+			return null;
+		}
+		Map<String, Object> res = new HashMap<>(properties.size());
+		Enumeration<String> keys = properties.keys();
+		while (keys.hasMoreElements()) {
+			String key = keys.nextElement();
+			res.put(key, properties.get(key));
+		}
+		return res;
+	}
+
 	/**
 	 * Get a string property from this map, expecting to find it, or
 	 * <code>null</code> if not found.
@@ -236,6 +251,34 @@ public class LangUtils {
 		return values;
 	}
 
+	/** Size of an {@link Iterable}, optimised if it is a {@link Collection}. */
+	public static int size(Iterable<?> iterable) {
+		if (iterable instanceof Collection)
+			return ((Collection<?>) iterable).size();
+
+		int size = 0;
+		for (Iterator<?> it = iterable.iterator(); it.hasNext(); size++)
+			it.next();
+		return size;
+	}
+
+	public static <T> T getAt(Iterable<T> iterable, int index) {
+		if (iterable instanceof List) {
+			List<T> lst = ((List<T>) iterable);
+			if (index >= lst.size())
+				throw new IllegalArgumentException("Index " + index + " is not available (size is " + lst.size() + ")");
+			return lst.get(index);
+		}
+		int i = 0;
+		for (Iterator<T> it = iterable.iterator(); it.hasNext(); i++) {
+			if (i == index)
+				return it.next();
+			else
+				it.next();
+		}
+		throw new IllegalArgumentException("Index " + index + " is not available (size is " + i + ")");
+	}
+
 	/*
 	 * EXCEPTIONS
 	 */