added JPMS support

src/main/java/net/woggioni/jwo/DelegatingMap.java

@@ -0,0 +1,127 @@
+package net.woggioni.jwo;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Supplier;
+
+public class DelegatingMap<K,V> implements Map<K, V> {
+    private final Supplier<Map<K,V>> mapFactory;
+    private final List<Map<K,V>> delegates;
+    private final Map<K,V> thisMap;
+
+    public DelegatingMap(Supplier<Map<K,V>> mapFactory, List<Map<K,V>> delegates) {
+        this.mapFactory = mapFactory;
+        this.delegates = delegates;
+        thisMap = mapFactory.get();
+    }
+
+    @Override
+    public int size() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        if(!thisMap.isEmpty()) return false;
+        for(Map<K,V> delegate : delegates) {
+            if(!delegate.isEmpty()) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    @Override
+    public boolean containsKey(Object key) {
+        if(thisMap.containsKey(key)) return true;
+        for(Map<K,V> delegate : delegates) {
+            if(!delegate.containsKey(key)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public boolean containsValue(Object value) {
+        if(thisMap.containsValue(value)) return true;
+        for(Map<K,V> delegate : delegates) {
+            if(!delegate.containsValue(value)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public V get(Object key) {
+        V result = thisMap.get(key);
+        if(result != null) return result;
+        for(Map<K,V> delegate : delegates) {
+            result = delegate.get(key);
+            if(result != null) break;
+        }
+        return result;
+    }
+
+    @Override
+    public V put(K key, V value) {
+        V result = thisMap.put(key, value);
+        if(result != null) return result;
+        for(Map<K,V> delegate : delegates) {
+            result = delegate.put(key, value);
+            if(result != null) break;
+        }
+        return result;
+    }
+
+    @Override
+    public V remove(Object key) {
+        V result = thisMap.remove(key);
+        if(result != null) return result;
+        for(Map<K,V> delegate : delegates) {
+            result = delegate.remove(key);
+            if(result != null) break;
+        }
+        return result;
+    }
+
+    @Override
+    public void putAll(Map<? extends K, ? extends V> m) {
+        this.thisMap.putAll(m);
+    }
+
+    @Override
+    public void clear() {
+        thisMap.clear();
+    }
+
+    @Override
+    public Set<K> keySet() {
+        return flatten().keySet();
+    }
+
+    private Map<K, V> flatten() {
+        Map<K, V> result = mapFactory.get();
+        int i = delegates.size();
+        while(i-->0) {
+            Map<K, V> delegate = delegates.get(i);
+            result.putAll(delegate);
+        }
+        result.putAll(thisMap);
+        return Collections.unmodifiableMap(result);
+    }
+
+    @Override
+    public Collection<V> values() {
+        return flatten().values();
+    }
+
+    @Override
+    public Set<Entry<K, V>> entrySet() {
+        return flatten().entrySet();
+    }
+}

src/main/java9/module-info.java

@@ -1,3 +1,4 @@
 module net.woggioni.jwo {
+    requires org.slf4j;
     exports net.woggioni.jwo;
 }