1 /*

     2  * Copyright (c) 2018, 2019, 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.

     8  *

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

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

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

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

    13  * accompanied this code).

    14  *

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

    16  * 2 along with this work; if not, write to the Free Software Foundation,

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

    18  *

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

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

    21  * questions.

    22  */

    23 

    24 

    25 package org.graalvm.util;

    26 

    27 import java.io.ByteArrayInputStream;

    28 import java.io.ByteArrayOutputStream;

    29 import java.io.IOException;

    30 import java.util.LinkedHashMap;

    31 import java.util.Map;

    32 

    33 /**

    34  * Facilities for encoding/decoding a set of options to/from a byte array.

    35  */

    36 public final class OptionsEncoder {

    37 

    38     private OptionsEncoder() {

    39     }

    40 

    41     /**

    42      * Determines if {@code value} is supported by {@link #encode(Map)}.

    43      */

    44     public static boolean isValueSupported(Object value) {

    45         return TypedDataOutputStream.isValueSupported(value);

    46     }

    47 

    48     /**

    49      * Encodes {@code options} into a byte array.

    50      *

    51      * @throws IllegalArgumentException if any value in {@code options} is not

    52      *             {@linkplain #isValueSupported(Object) supported}

    53      */

    54     public static byte[] encode(final Map<String, Object> options) {

    55         try (ByteArrayOutputStream baout = new ByteArrayOutputStream()) {

    56             try (TypedDataOutputStream out = new TypedDataOutputStream(baout)) {

    57                 out.writeInt(options.size());

    58                 for (Map.Entry<String, Object> e : options.entrySet()) {

    59                     out.writeUTF(e.getKey());

    60                     try {

    61                         out.writeTypedValue(e.getValue());

    62                     } catch (IllegalArgumentException iae) {

    63                         throw new IllegalArgumentException(String.format("Key: %s, Value: %s, Value type: %s",

    64                                         e.getKey(), e.getValue(), e.getValue().getClass()), iae);

    65                     }

    66                 }

    67             }

    68             return baout.toByteArray();

    69         } catch (IOException ioe) {

    70             throw new IllegalArgumentException(ioe);

    71         }

    72     }

    73 

    74     /**

    75      * Decodes {@code input} into a name/value map.

    76      *

    77      * @throws IllegalArgumentException if {@code input} cannot be decoded

    78      */

    79     public static Map<String, Object> decode(byte[] input) {

    80         Map<String, Object> res = new LinkedHashMap<>();

    81         try (TypedDataInputStream in = new TypedDataInputStream(new ByteArrayInputStream(input))) {

    82             final int size = in.readInt();

    83             for (int i = 0; i < size; i++) {

    84                 final String key = in.readUTF();

    85                 final Object value = in.readTypedValue();

    86                 res.put(key, value);

    87             }

    88             if (in.available() != 0) {

    89                 throw new IllegalArgumentException(in.available() + " undecoded bytes");

    90             }

    91         } catch (IOException ioe) {

    92             throw new IllegalArgumentException(ioe);

    93         }

    94         return res;

    95     }

    96 }