X-Git-Url: https://git.argeo.org/?a=blobdiff_plain;f=org.argeo.cms%2Fsrc%2Forg%2Fargeo%2Fcms%2Futil%2FLangUtils.java;h=67748ccd7121ce2cbae24c428f12b6840f55fde7;hb=HEAD;hp=0e214271d7a612642b35e0af3f1b971a56f89280;hpb=55870eba50d8b28e72a3102fd18a17a6f23f7bad;p=lgpl%2Fargeo-commons.git

diff --git a/org.argeo.cms/src/org/argeo/cms/util/LangUtils.java b/org.argeo.cms/src/org/argeo/cms/util/LangUtils.java
index 0e214271d..67748ccd7 100644
--- a/org.argeo.cms/src/org/argeo/cms/util/LangUtils.java
+++ b/org.argeo.cms/src/org/argeo/cms/util/LangUtils.java
@@ -12,13 +12,16 @@ import java.time.temporal.ChronoUnit;
 import java.time.temporal.Temporal;
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Collections;
 import java.util.Dictionary;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.Hashtable;
 import java.util.Iterator;
+import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.Properties;
 
 import javax.naming.InvalidNameException;
@@ -27,37 +30,16 @@ import javax.naming.ldap.LdapName;
 /** Utilities around Java basic features. */
 public class LangUtils {
 	/*
-	 * NON-API OSGi
+	 * OBJECTS and STRINGS
 	 */
 	/**
-	 * Returns an array with the names of the provided classes. Useful when
-	 * registering services with multiple interfaces in OSGi.
+	 * Whether this {@link String} is <code>null</null>, empty, or only white
+	 * spaces.
 	 */
-	public static String[] names(Class<?>... clzz) {
-		String[] res = new String[clzz.length];
-		for (int i = 0; i < clzz.length; i++)
-			res[i] = clzz[i].getName();
-		return res;
+	public static boolean isEmpty(String str) {
+		return str == null || "".equals(str.strip());
 	}
 
-//	/*
-//	 * MAP
-//	 */
-//	/**
-//	 * Creates a new {@link Map} with one key-value pair. Key should not be null,
-//	 * but if the value is null, it returns an empty {@link Map}.
-//	 * 
-//	 * @deprecated Use {@link Collections#singletonMap(Object, Object)} instead.
-//	 */
-//	@Deprecated
-//	public static Map<String, Object> map(String key, Object value) {
-//		assert key != null;
-//		HashMap<String, Object> props = new HashMap<>();
-//		if (value != null)
-//			props.put(key, value);
-//		return props;
-//	}
-
 	/*
 	 * DICTIONARY
 	 */
@@ -279,6 +261,24 @@ public class LangUtils {
 		throw new IllegalArgumentException("Index " + index + " is not available (size is " + i + ")");
 	}
 
+	public static <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map) {
+		return sortByValue(map, false);
+	}
+
+	public static <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map, boolean descending) {
+		List<Entry<K, V>> list = new ArrayList<>(map.entrySet());
+		list.sort(Entry.comparingByValue());
+		if (descending)
+			Collections.reverse(list);
+
+		Map<K, V> result = new LinkedHashMap<>();
+		for (Entry<K, V> entry : list) {
+			result.put(entry.getKey(), entry.getValue());
+		}
+
+		return result;
+	}
+
 	/*
 	 * EXCEPTIONS
 	 */
@@ -323,6 +323,20 @@ public class LangUtils {
 		return count > 1 ? count + " seconds" : count + " second";
 	}
 
+	/*
+	 * NON-API OSGi
+	 */
+	/**
+	 * Returns an array with the names of the provided classes. Useful when
+	 * registering services with multiple interfaces in OSGi.
+	 */
+	public static String[] names(Class<?>... clzz) {
+		String[] res = new String[clzz.length];
+		for (int i = 0; i < clzz.length; i++)
+			res[i] = clzz[i].getName();
+		return res;
+	}
+
 	/** Singleton constructor. */
 	private LangUtils() {