Migrated source code from Simantics SVN

[simantics/platform.git] / bundles / org.simantics.diagram / src / org / simantics / diagram / symbolcontribution / AdaptablePair.java

diff --git a/bundles/org.simantics.diagram/src/org/simantics/diagram/symbolcontribution/AdaptablePair.java b/bundles/org.simantics.diagram/src/org/simantics/diagram/symbolcontribution/AdaptablePair.java
new file mode 100644 (file)
index 0000000..3ea3f28
--- /dev/null
+++ b/bundles/org.simantics.diagram/src/org/simantics/diagram/symbolcontribution/AdaptablePair.java
@@ -0,0 +1,83 @@
+/*******************************************************************************\r
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management\r
+ * in Industry THTH ry.\r
+ * All rights reserved. This program and the accompanying materials\r
+ * are made available under the terms of the Eclipse Public License v1.0\r
+ * which accompanies this distribution, and is available at\r
+ * http://www.eclipse.org/legal/epl-v10.html\r
+ *\r
+ * Contributors:\r
+ *     VTT Technical Research Centre of Finland - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.diagram.symbolcontribution;\r
+\r
+import org.eclipse.core.runtime.IAdaptable;\r
+\r
+/**\r
+ * A basic pair structure that implements IAdaptable. It tries to adapt the\r
+ * paired objects to the requested class in order (first, second).\r
+ * \r
+ * @author Tuukka Lehtonen\r
+ * \r
+ * @param <T1> type of first\r
+ * @param <T2> type of second\r
+ */\r
+final class AdaptablePair<T1, T2> implements IAdaptable {\r
+    public final T1 first;\r
+    public final T2 second;\r
+    private final int hash;\r
+\r
+    public static <T1, T2> AdaptablePair<T1, T2> make(T1 t1, T2 t2) {\r
+        return new AdaptablePair<T1, T2>(t1, t2);\r
+    }\r
+\r
+    public AdaptablePair(T1 first, T2 second) {\r
+        this.first = first;\r
+        this.second = second;\r
+        this.hash = makeHash();\r
+    }\r
+\r
+    @Override\r
+    public boolean equals(Object obj) {\r
+        if (obj == null)\r
+            return false;\r
+        if (!(obj.getClass().equals(this.getClass())))\r
+            return false;\r
+        AdaptablePair<?, ?> other = (AdaptablePair<?, ?>) obj;\r
+        if (other.first != first && (other.first == null || !other.first.equals(first)))\r
+            return false;\r
+        if (other.second != second && (other.second == null || !other.second.equals(second)))\r
+            return false;\r
+        return true;\r
+    }\r
+\r
+    @Override\r
+    public int hashCode() {\r
+        return hash;\r
+    }\r
+\r
+    @Override\r
+    public String toString() {\r
+        return "<"+first+", "+second+">";\r
+    }\r
+\r
+    private int makeHash() {\r
+        return (first == null ? 0 : first.hashCode()) + (second == null ? 0 : second.hashCode())*31;\r
+    }\r
+\r
+    private Object adapt(Object o, Class<?> clazz) {\r
+        if (clazz.isInstance(o))\r
+            return o;\r
+        if (o instanceof IAdaptable)\r
+            return ((IAdaptable) o).getAdapter(clazz);\r
+        return null;\r
+    }\r
+\r
+    @SuppressWarnings("rawtypes")\r
+    @Override\r
+    public Object getAdapter(Class adapter) {\r
+        Object o = adapt(first, adapter);\r
+        return (o == null) ? adapt(second, adapter) : o;\r
+    }\r
+\r
+}\r