src/java.base/share/classes/java/lang/package-info.java
author darcy
Wed, 25 Apr 2018 22:12:06 -0700
changeset 49895 661ef62a6618
parent 49508 8f041818aca9
permissions -rw-r--r--
8200478: For boxing conversion javac uses Long.valueOf which does not guarantee caching according to its javadoc Reviewed-by: bpb

/*
 * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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/**
 * Provides classes that are fundamental to the design of the Java
 * programming language. The most important classes are {@code
 * Object}, which is the root of the class hierarchy, and {@code
 * Class}, instances of which represent classes at run time.
 *
 * <p>Frequently it is necessary to represent a value of primitive
 * type as if it were an object. The wrapper classes {@code Boolean},
 * {@code Character}, {@code Integer}, {@code Long}, {@code Float},
 * and {@code Double} serve this purpose.  An object of type {@code
 * Double}, for example, contains a field whose type is double,
 * representing that value in such a way that a reference to it can be
 * stored in a variable of reference type.  These classes also provide
 * a number of methods for converting among primitive values, as well
 * as supporting such standard methods as equals and hashCode.  The
 * {@code Void} class is a non-instantiable class that holds a
 * reference to a {@code Class} object representing the type void.
 *
 * <p>The class {@code Math} provides commonly used mathematical
 * functions such as sine, cosine, and square root. The classes {@code
 * String}, {@code StringBuffer}, and {@code StringBuilder} similarly
 * provide commonly used operations on character strings.
 *
 * <p>Classes {@code ClassLoader}, {@code Process}, {@code
 * ProcessBuilder}, {@code Runtime}, {@code SecurityManager}, and
 * {@code System} provide "system operations" that manage the dynamic
 * loading of classes, creation of external processes, host
 * environment inquiries such as the time of day, and enforcement of
 * security policies.
 *
 * <p>Class {@code Throwable} encompasses objects that may be thrown
 * by the {@code throw} statement. Subclasses of {@code Throwable}
 * represent errors and exceptions.
 *
 * <a id="charenc"></a>
 * <h2>Character Encodings</h2>
 *
 * The specification of the {@link java.nio.charset.Charset
 * java.nio.charset.Charset} class describes the naming conventions
 * for character encodings as well as the set of standard encodings
 * that must be supported by every implementation of the Java
 * platform.
 *
 * @since 1.0
 */
package java.lang;