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.
   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 import java.lang.module.ModuleDescriptor;
  25 import java.lang.module.ModuleFinder;
  26 import java.lang.module.ModuleReader;
  27 import java.lang.module.ModuleReference;
  28 import java.net.URI;
  29 import java.util.HashMap;
  30 import java.util.HashSet;
  31 import java.util.Map;
  32 import java.util.Objects;
  33 import java.util.Optional;
  34 import java.util.Set;
  35 
  36 
  37 /**
  38  * This class consists exclusively of static utility methods that are useful
  39  * for creating tests for modules.
  40  */
  41 
  42 public final class ModuleUtils {
  43     private ModuleUtils() { }
  44 
  45 
  46     /**
  47      * Returns a ModuleFinder that finds modules with the given module
  48      * descriptors.
  49      */
  50     static ModuleFinder finderOf(ModuleDescriptor... descriptors) {
  51 
  52         // Create a ModuleReference for each module
  53         Map<String, ModuleReference> namesToReference = new HashMap<>();
  54 
  55         for (ModuleDescriptor descriptor : descriptors) {
  56             String name = descriptor.name();
  57 
  58             URI uri = URI.create("module:/" + name);
  59 
  60             ModuleReference mref = new ModuleReference(descriptor, uri) {
  61                 @Override
  62                 public ModuleReader open() {
  63                     throw new UnsupportedOperationException();
  64                 }
  65             };
  66 
  67             namesToReference.put(name, mref);
  68         }
  69 
  70         return new ModuleFinder() {
  71             @Override
  72             public Optional<ModuleReference> find(String name) {
  73                 Objects.requireNonNull(name);
  74                 return Optional.ofNullable(namesToReference.get(name));
  75             }
  76             @Override
  77             public Set<ModuleReference> findAll() {
  78                 return new HashSet<>(namesToReference.values());
  79             }
  80         };
  81     }
  82 
  83 }