1 /*

     2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package sun.java2d.marlin;

    27 

    28 import java.util.ArrayDeque;

    29 import java.util.Arrays;

    30 import static sun.java2d.marlin.MarlinUtils.logException;

    31 import static sun.java2d.marlin.MarlinUtils.logInfo;

    32 

    33 final class ByteArrayCache implements MarlinConst {

    34 

    35     private final int arraySize;

    36     private final ArrayDeque<byte[]> byteArrays;

    37     // stats

    38     private int getOp = 0;

    39     private int createOp = 0;

    40     private int returnOp = 0;

    41 

    42     void dumpStats() {

    43         if (getOp > 0) {

    44             logInfo("ByteArrayCache[" + arraySize + "]: get: " + getOp

    45                     + " created: " + createOp + " - returned: " + returnOp

    46                     + " :: cache size: " + byteArrays.size());

    47         }

    48     }

    49 

    50     ByteArrayCache(final int arraySize) {

    51         this.arraySize = arraySize;

    52         // small but enough: almost 1 cache line

    53         this.byteArrays = new ArrayDeque<byte[]>(6);

    54     }

    55 

    56     byte[] getArray() {

    57         if (doStats) {

    58             getOp++;

    59         }

    60 

    61         // use cache:

    62         final byte[] array = byteArrays.pollLast();

    63         if (array != null) {

    64             return array;

    65         }

    66 

    67         if (doStats) {

    68             createOp++;

    69         }

    70 

    71         return new byte[arraySize];

    72     }

    73 

    74     void putDirtyArray(final byte[] array, final int length) {

    75         if (length != arraySize) {

    76             if (doChecks) {

    77                 System.out.println("ArrayCache: bad length = " + length);

    78             }

    79             return;

    80         }

    81         if (doStats) {

    82             returnOp++;

    83         }

    84 

    85         // NO clean-up of array data = DIRTY ARRAY

    86 

    87         if (doCleanDirty) {

    88             // Force zero-fill dirty arrays:

    89             Arrays.fill(array, 0, array.length, BYTE_0);

    90         }

    91 

    92         // fill cache:

    93         byteArrays.addLast(array);

    94     }

    95 

    96     void putArray(final byte[] array, final int length,

    97                   final int fromIndex, final int toIndex)

    98     {

    99         if (length != arraySize) {

   100             if (doChecks) {

   101                 System.out.println("ArrayCache: bad length = " + length);

   102             }

   103             return;

   104         }

   105         if (doStats) {

   106             returnOp++;

   107         }

   108 

   109         // clean-up array of dirty part[fromIndex; toIndex[

   110         fill(array, fromIndex, toIndex, BYTE_0);

   111 

   112         // fill cache:

   113         byteArrays.addLast(array);

   114     }

   115 

   116     static void fill(final byte[] array, final int fromIndex,

   117                      final int toIndex, final byte value)

   118     {

   119         // clear array data:

   120         /*

   121          * Arrays.fill is faster than System.arraycopy(empty array)

   122          * or Unsafe.setMemory(byte 0)

   123          */

   124         if (toIndex != 0) {

   125             Arrays.fill(array, fromIndex, toIndex, value);

   126         }

   127 

   128         if (doChecks) {

   129             check(array, 0, array.length, value);

   130         }

   131     }

   132 

   133     static void check(final byte[] array, final int fromIndex,

   134                       final int toIndex, final byte value)

   135     {

   136         if (doChecks) {

   137             // check zero on full array:

   138             for (int i = fromIndex; i < toIndex; i++) {

   139                 if (array[i] != value) {

   140                     logException("Invalid array value at " + i + "\n"

   141                             + Arrays.toString(array), new Throwable());

   142 

   143                     // ensure array is correctly filled:

   144                     Arrays.fill(array, value);

   145 

   146                     return;

   147                 }

   148             }

   149         }

   150     }

   151 }