--- a/src/java.base/share/classes/java/util/Properties.java Mon Oct 30 07:06:49 2017 -0700
+++ b/src/java.base/share/classes/java/util/Properties.java Mon Oct 30 16:16:01 2017 -0700
@@ -122,6 +122,10 @@
* <p>This class is thread-safe: multiple threads can share a single
* {@code Properties} object without the need for external synchronization.
*
+ * @apiNote
+ * The {@code Properties} class does not inherit the concept of a load factor
+ * from its superclass, {@code Hashtable}.
+ *
* @author Arthur van Hoff
* @author Michael McCloskey
* @author Xueming Shen
@@ -148,25 +152,49 @@
* simple read operations. Writes and bulk operations remain synchronized,
* as in Hashtable.
*/
- private transient ConcurrentHashMap<Object, Object> map =
- new ConcurrentHashMap<>(8);
+ private transient ConcurrentHashMap<Object, Object> map;
/**
* Creates an empty property list with no default values.
+ *
+ * @implNote The initial capacity of a {@code Properties} object created
+ * with this constructor is unspecified.
*/
public Properties() {
- this(null);
+ this(null, 8);
+ }
+
+ /**
+ * Creates an empty property list with no default values, and with an
+ * initial size accommodating the specified number of elements without the
+ * need to dynamically resize.
+ *
+ * @param initialCapacity the {@code Properties} will be sized to
+ * accommodate this many elements
+ * @throws IllegalArgumentException if the initial capacity is less than
+ * zero.
+ */
+ public Properties(int initialCapacity) {
+ this(null, initialCapacity);
}
/**
* Creates an empty property list with the specified defaults.
*
+ * @implNote The initial capacity of a {@code Properties} object created
+ * with this constructor is unspecified.
+ *
* @param defaults the defaults.
*/
public Properties(Properties defaults) {
+ this(defaults, 8);
+ }
+
+ private Properties(Properties defaults, int initialCapacity) {
// use package-private constructor to
// initialize unused fields with dummy values
super((Void) null);
+ map = new ConcurrentHashMap<>(initialCapacity);
this.defaults = defaults;
}