--- /dev/null
+/*******************************************************************************\r
+ * Copyright (c) 2005, 2007 IBM Corporation and others.\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
+ * IBM Corporation - initial API and implementation\r
+ *******************************************************************************/\r
+package org.simantics.browsing.ui;\r
+\r
+import java.util.Arrays;\r
+\r
+import org.eclipse.core.runtime.Assert;\r
+import org.eclipse.core.runtime.IAdaptable;\r
+\r
+/**\r
+ * A {@link GraphExplorer} tree {@link NodeContext} path denotes a model element\r
+ * in a tree viewer. Tree path objects have value semantics. A model element is\r
+ * represented by a path of elements in the tree from the root element to the\r
+ * leaf element.\r
+ * <p>\r
+ * Clients may instantiate this class. Not intended to be subclassed.\r
+ * </p>\r
+ * \r
+ * <p>\r
+ * Directly imitated for the Simantics browsing framework from JFace\r
+ * <code>org.eclipse.jface.viewer.TreePath</code> class.\r
+ * </p>\r
+ * \r
+ * @author Tuukka Lehtonen\r
+ */\r
+public final class NodeContextPath implements IAdaptable {\r
+\r
+ public static final NodeContextPath[] NONE = {};\r
+\r
+ /**\r
+ * Constant for representing an empty tree path.\r
+ */\r
+ public static final NodeContextPath EMPTY = new NodeContextPath(NodeContext.NONE);\r
+\r
+ private final NodeContext[] segments;\r
+\r
+ private int hash;\r
+\r
+ /**\r
+ * Constructs a path identifying a leaf node in a tree.\r
+ * \r
+ * @param segments\r
+ * path of elements to a leaf node in a tree, starting with the\r
+ * root element\r
+ */\r
+ public NodeContextPath(NodeContext... segments) {\r
+ Assert.isNotNull(segments);\r
+ for (int i = 0; i < segments.length; i++) {\r
+ Assert.isNotNull(segments[i]);\r
+ }\r
+ this.segments = segments;\r
+ }\r
+\r
+ /**\r
+ * Returns the element at the specified index in this path.\r
+ * \r
+ * @param index\r
+ * index of element to return\r
+ * @return element at the specified index\r
+ */\r
+ public NodeContext getSegment(int index) {\r
+ return segments[index];\r
+ }\r
+\r
+ /**\r
+ * Returns the number of elements in this path.\r
+ * \r
+ * @return the number of elements in this path\r
+ */\r
+ public int getSegmentCount() {\r
+ return segments.length;\r
+ }\r
+\r
+ /**\r
+ * Returns the first element in this path, or <code>null</code> if this\r
+ * path has no segments.\r
+ * \r
+ * @return the first element in this path\r
+ */\r
+ public NodeContext getFirstSegment() {\r
+ if (segments.length == 0) {\r
+ return null;\r
+ }\r
+ return segments[0];\r
+ }\r
+\r
+ /**\r
+ * Returns the last element in this path, or <code>null</code> if this\r
+ * path has no segments.\r
+ * \r
+ * @return the last element in this path\r
+ */\r
+ public NodeContext getLastSegment() {\r
+ if (segments.length == 0) {\r
+ return null;\r
+ }\r
+ return segments[segments.length - 1];\r
+ }\r
+\r
+ /**\r
+ * @return all the segments in the path as an array\r
+ */\r
+ public NodeContext[] getSegments() {\r
+ if (segments.length == 0)\r
+ return segments;\r
+ return Arrays.copyOf(segments, segments.length);\r
+ }\r
+\r
+ /*\r
+ * (non-Javadoc)\r
+ * \r
+ * @see java.lang.Object#equals(java.lang.Object)\r
+ */\r
+ public boolean equals(Object other) {\r
+ if (!(other instanceof NodeContextPath)) {\r
+ return false;\r
+ }\r
+ return equals((NodeContextPath) other);\r
+ }\r
+\r
+ /**\r
+ * (non-Javadoc)\r
+ * \r
+ * @see java.lang.Object#hashCode()\r
+ */\r
+ public int hashCode() {\r
+ if (hash == 0) {\r
+ hash = hashCode0();\r
+ }\r
+ return hash;\r
+ }\r
+\r
+ /**\r
+ * Returns a hash code computed from the hash codes of the segments, using\r
+ * the given comparer to compute the hash codes of the segments.\r
+ * \r
+ * @param comparer\r
+ * comparer to use or <code>null</code> if the segments' hash\r
+ * codes should be computed by calling their hashCode() methods.\r
+ * @return the computed hash code\r
+ */\r
+ private int hashCode0() {\r
+ int result = 0;\r
+ for (int i = 0; i < segments.length; i++) {\r
+ result += segments[i].hashCode();\r
+ }\r
+ return result;\r
+ }\r
+\r
+ /**\r
+ * Returns whether this path is equivalent to the given path using the\r
+ * specified comparer to compare individual elements.\r
+ * \r
+ * @param otherPath\r
+ * tree path to compare to\r
+ * @param comparer\r
+ * comparator to use or <code>null</code> if segments should be\r
+ * compared using equals()\r
+ * @return whether the paths are equal\r
+ */\r
+ public boolean equals(NodeContextPath otherPath) {\r
+ if (otherPath == null) {\r
+ return false;\r
+ }\r
+ if (segments.length != otherPath.segments.length) {\r
+ return false;\r
+ }\r
+ for (int i = 0; i < segments.length; i++) {\r
+ if (!segments[i].equals(otherPath.segments[i])) {\r
+ return false;\r
+ }\r
+ }\r
+ return true;\r
+ }\r
+\r
+ /**\r
+ * Returns whether this path starts with the same segments as the given\r
+ * path, using the given comparer to compare segments.\r
+ * \r
+ * @param treePath\r
+ * path to compare to\r
+ * @param comparer\r
+ * the comparer to use, or <code>null</code> if equals() should\r
+ * be used to compare segments\r
+ * @return whether the given path is a prefix of this path, or the same as\r
+ * this path\r
+ */\r
+ public boolean startsWith(NodeContextPath treePath) {\r
+ int thisSegmentCount = getSegmentCount();\r
+ int otherSegmentCount = treePath.getSegmentCount();\r
+ if (otherSegmentCount == thisSegmentCount) {\r
+ return equals(treePath);\r
+ }\r
+ if (otherSegmentCount > thisSegmentCount) {\r
+ return false;\r
+ }\r
+ for (int i = 0; i < otherSegmentCount; i++) {\r
+ Object otherSegment = treePath.getSegment(i);\r
+ if (!otherSegment.equals(segments[i])) {\r
+ return false;\r
+ }\r
+ }\r
+ return true;\r
+ }\r
+\r
+ /**\r
+ * Returns a copy of this tree path with one segment removed from the end,\r
+ * or <code>null</code> if this tree path has no segments.\r
+ * @return a tree path\r
+ */\r
+ public NodeContextPath getParentPath() {\r
+ int segmentCount = getSegmentCount();\r
+ if (segmentCount < 1) {\r
+ return null;\r
+ } else if (segmentCount == 1) {\r
+ return EMPTY;\r
+ }\r
+ NodeContext[] parentSegments = new NodeContext[segmentCount - 1];\r
+ System.arraycopy(segments, 0, parentSegments, 0, segmentCount - 1);\r
+ return new NodeContextPath(parentSegments);\r
+ }\r
+\r
+ /**\r
+ * Returns a copy of this tree path with the given segment added at the end.\r
+ * @param newSegment \r
+ * @return a tree path\r
+ */\r
+ public NodeContextPath createChildPath(NodeContext newSegment) {\r
+ int segmentCount = getSegmentCount();\r
+ NodeContext[] childSegments = new NodeContext[segmentCount + 1];\r
+ if(segmentCount>0) {\r
+ System.arraycopy(segments, 0, childSegments, 0, segmentCount);\r
+ }\r
+ childSegments[segmentCount] = newSegment;\r
+ return new NodeContextPath(childSegments);\r
+ }\r
+\r
+ @SuppressWarnings("rawtypes")\r
+ @Override\r
+ public Object getAdapter(Class adapter) {\r
+ if (NodeContext.class == adapter)\r
+ return getLastSegment();\r
+ NodeContext last = getLastSegment();\r
+ if (last instanceof IAdaptable)\r
+ return ((IAdaptable) last).getAdapter(adapter);\r
+ return null;\r
+ }\r
+\r
+}\r
Code Review / simantics / platform.git / blobdiff