import java.time.ZonedDateTime;
import java.time.temporal.ChronoUnit;
import java.time.temporal.Temporal;
+import java.util.ArrayList;
+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;
import javax.naming.InvalidNameException;
import javax.naming.ldap.LdapName;
+/** Utilities around Java basic features. */
public class LangUtils {
/*
* NON-API OSGi
return res;
}
+// /*
+// * 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
*/
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.
+ */
+ public static String get(Map<String, ?> map, String key) {
+ Object res = map.get(key);
+ if (res == null)
+ return null;
+ return res.toString();
+ }
+
+ /**
+ * Get a string property from this map, expecting to find it.
+ *
+ * @throws IllegalArgumentException if the key was not found
+ */
+ public static String getNotNull(Map<String, ?> map, String key) {
+ Object res = map.get(key);
+ if (res == null)
+ throw new IllegalArgumentException("Map " + map + " should contain key " + key);
+ return res.toString();
+ }
+
/**
* Wraps the keys of the provided {@link Dictionary} as an {@link Iterable}.
*/
return res;
}
+ /*
+ * COLLECTIONS
+ */
+ /**
+ * Convert a comma-separated separated {@link String} or a {@link String} array
+ * to a {@link List} of {@link String}, trimming them. Useful to quickly
+ * interpret OSGi services properties.
+ *
+ * @return a {@link List} containing the trimmed {@link String}s, or an empty
+ * {@link List} if the argument was <code>null</code>.
+ */
+ public static List<String> toStringList(Object value) {
+ List<String> values = new ArrayList<>();
+ if (value == null)
+ return values;
+ String[] arr;
+ if (value instanceof String) {
+ arr = ((String) value).split(",");
+ } else if (value instanceof String[]) {
+ arr = (String[]) value;
+ } else {
+ throw new IllegalArgumentException("Unsupported value type " + value.getClass());
+ }
+ for (String str : arr) {
+ values.add(str.trim());
+ }
+ 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
*/