src/java.base/share/classes/java/nio/ByteBufferAs-X-Buffer.java.template - master - githubmirror/jdk11u-dev

src/java.base/share/classes/java/nio/ByteBufferAs-X-Buffer.java.template
250 строк7 KB
Rob McKenna
8234841: Enhance buffering of byte buffers
30 мар 2020, 07:13
30 мар 2020, 07:13e0a9435
/*
 * Copyright (c) 2000, 2016, 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.
 */

#warn This file is preprocessed before being compiled

package java.nio;

import jdk.internal.misc.Unsafe;


class ByteBufferAs$Type$Buffer$RW$$BO$                  // package-private
    extends {#if[ro]?ByteBufferAs}$Type$Buffer{#if[ro]?$BO$}
{

#if[rw]

    protected final ByteBuffer bb;

#end[rw]

    ByteBufferAs$Type$Buffer$RW$$BO$(ByteBuffer bb) {   // package-private
#if[rw]
        super(-1, 0,
              bb.remaining() >> $LG_BYTES_PER_VALUE$,
              bb.remaining() >> $LG_BYTES_PER_VALUE$);
        this.bb = bb;
        // enforce limit == capacity
        int cap = this.capacity();
        this.limit(cap);
        int pos = this.position();
        assert (pos <= cap);
        address = bb.address;
#else[rw]
        super(bb);
#end[rw]
    }

    ByteBufferAs$Type$Buffer$RW$$BO$(ByteBuffer bb,
                                     int mark, int pos, int lim, int cap,
                                     long addr)
    {
#if[rw]
        super(mark, pos, lim, cap);
        this.bb = bb;
        address = addr;
        assert address >= bb.address;
#else[rw]
        super(bb, mark, pos, lim, cap, addr);
#end[rw]
    }

    @Override
    Object base() {
        return bb.hb;
    }

    public $Type$Buffer slice() {
        int pos = this.position();
        int lim = this.limit();
        int rem = (pos <= lim ? lim - pos : 0);
        long addr = byteOffset(pos);
        return new ByteBufferAs$Type$Buffer$RW$$BO$(bb, -1, 0, rem, rem, addr);
    }

    public $Type$Buffer duplicate() {
        return new ByteBufferAs$Type$Buffer$RW$$BO$(bb,
                                                    this.markValue(),
                                                    this.position(),
                                                    this.limit(),
                                                    this.capacity(),
                                                    address);
    }

    public $Type$Buffer asReadOnlyBuffer() {
#if[rw]
        return new ByteBufferAs$Type$BufferR$BO$(bb,
                                                 this.markValue(),
                                                 this.position(),
                                                 this.limit(),
                                                 this.capacity(),
                                                 address);
#else[rw]
        return duplicate();
#end[rw]
    }

#if[rw]

    private int ix(int i) {
        int off = (int) (address - bb.address);
        return (i << $LG_BYTES_PER_VALUE$) + off;
    }

    protected long byteOffset(long i) {
        return (i << $LG_BYTES_PER_VALUE$) + address;
    }

    public $type$ get() {
        $memtype$ x = UNSAFE.get$Memtype$Unaligned(bb.hb, byteOffset(nextGetIndex()),
            {#if[boB]?true:false});
        return $fromBits$(x);
    }

    public $type$ get(int i) {
        $memtype$ x = UNSAFE.get$Memtype$Unaligned(bb.hb, byteOffset(checkIndex(i)),
            {#if[boB]?true:false});
        return $fromBits$(x);
    }

#if[streamableType]
   $type$ getUnchecked(int i) {
        $memtype$ x = UNSAFE.get$Memtype$Unaligned(bb.hb, byteOffset(i),
            {#if[boB]?true:false});
        return $fromBits$(x);
    }
#end[streamableType]

#end[rw]

    public $Type$Buffer put($type$ x) {
#if[rw]
        $memtype$ y = $toBits$(x);
        UNSAFE.put$Memtype$Unaligned(bb.hb, byteOffset(nextPutIndex()), y,
            {#if[boB]?true:false});
        return this;
#else[rw]
        throw new ReadOnlyBufferException();
#end[rw]
    }

    public $Type$Buffer put(int i, $type$ x) {
#if[rw]
        $memtype$ y = $toBits$(x);
        UNSAFE.put$Memtype$Unaligned(bb.hb, byteOffset(checkIndex(i)), y,
            {#if[boB]?true:false});
        return this;
#else[rw]
        throw new ReadOnlyBufferException();
#end[rw]
    }

    public $Type$Buffer compact() {
#if[rw]
        int pos = position();
        int lim = limit();
        assert (pos <= lim);
        int rem = (pos <= lim ? lim - pos : 0);

        ByteBuffer db = bb.duplicate();
        db.limit(ix(lim));
        db.position(ix(0));
        ByteBuffer sb = db.slice();
        sb.position(pos << $LG_BYTES_PER_VALUE$);
        sb.compact();
        position(rem);
        limit(capacity());
        discardMark();
        return this;
#else[rw]
        throw new ReadOnlyBufferException();
#end[rw]
    }

    public boolean isDirect() {
        return bb.isDirect();
    }

    public boolean isReadOnly() {
        return {#if[rw]?false:true};
    }

#if[char]

    public String toString(int start, int end) {
        if ((end > limit()) || (start > end))
            throw new IndexOutOfBoundsException();
        try {
            int len = end - start;
            char[] ca = new char[len];
            CharBuffer cb = CharBuffer.wrap(ca);
            CharBuffer db = this.duplicate();
            db.position(start);
            db.limit(end);
            cb.put(db);
            return new String(ca);
        } catch (StringIndexOutOfBoundsException x) {
            throw new IndexOutOfBoundsException();
        }
    }


    // --- Methods to support CharSequence ---

    public CharBuffer subSequence(int start, int end) {
        int pos = position();
        int lim = limit();
        assert (pos <= lim);
        pos = (pos <= lim ? pos : lim);
        int len = lim - pos;

        if ((start < 0) || (end > len) || (start > end))
            throw new IndexOutOfBoundsException();
        return new ByteBufferAsCharBuffer$RW$$BO$(bb,
                                                  -1,
                                                  pos + start,
                                                  pos + end,
                                                  capacity(),
                                                  address);
    }

#end[char]


    public ByteOrder order() {
#if[boB]
        return ByteOrder.BIG_ENDIAN;
#end[boB]
#if[boL]
        return ByteOrder.LITTLE_ENDIAN;
#end[boL]
    }

#if[char]
    ByteOrder charRegionOrder() {
        return order();
    }
#end[char]
}