java.nio.ByteOrderクラスはバイトオーダー（ビッグエンディアン／リトルエンディアン）を表すクラスである。
実装はenumに限りなく近いものである。staticなインスタンスを２つ定義して，それぞれビッグエンディアンとリトルエンディアンを表す仕組みになっている。このクラスが設計された当時はenumがサポートされていなかったため，このような実装になったと思われる。
コンストラクタはprivateになっており，外部からインスタンスを作成することはできない。privateなインスタンス変数nameに名称を保持する。そして，staticなフィールドに自身のインスタンスを２つ持ち，それぞれ，”BIG_ENDIAN” ，”LITTLE_ENDIAN”という文字列をコンストラクタに渡している。
/*
* Copyright (c) 2000, 2013, 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.nio;
import jdk.internal.misc.Unsafe;
public final class ByteOrder {
private String name;
private ByteOrder(String name) {
this.name = name;
}
public static final ByteOrder BIG_ENDIAN
= new ByteOrder("BIG_ENDIAN");
public static final ByteOrder LITTLE_ENDIAN
= new ByteOrder("LITTLE_ENDIAN");
// Retrieve the native byte order. It's used early during bootstrap, and
// must be initialized after BIG_ENDIAN and LITTLE_ENDIAN.
private static final ByteOrder NATIVE_ORDER
= Unsafe.getUnsafe().isBigEndian()
? ByteOrder.BIG_ENDIAN : ByteOrder.LITTLE_ENDIAN;
public static ByteOrder nativeOrder() {
return NATIVE_ORDER;
}
public String toString() {
return name;
}
}
* Copyright (c) 2000, 2013, 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
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.nio;
import jdk.internal.misc.Unsafe;
public final class ByteOrder {
private String name;
private ByteOrder(String name) {
this.name = name;
}
public static final ByteOrder BIG_ENDIAN
= new ByteOrder("BIG_ENDIAN");
public static final ByteOrder LITTLE_ENDIAN
= new ByteOrder("LITTLE_ENDIAN");
// Retrieve the native byte order. It's used early during bootstrap, and
// must be initialized after BIG_ENDIAN and LITTLE_ENDIAN.
private static final ByteOrder NATIVE_ORDER
= Unsafe.getUnsafe().isBigEndian()
? ByteOrder.BIG_ENDIAN : ByteOrder.LITTLE_ENDIAN;
public static ByteOrder nativeOrder() {
return NATIVE_ORDER;
}
public String toString() {
return name;
}
}
ＪＹ情報システムズ 