1 files changed, 142 insertions, 0 deletions
diff --git a/lttng/org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/internal/tmf/core/trace/indexer/FlatArray.java b/lttng/org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/internal/tmf/core/trace/indexer/FlatArray.java
new file mode 100644
index 0000000000..de9d906888
--- /dev/null
+++ b/lttng/org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/internal/tmf/core/trace/indexer/FlatArray.java
@@ -0,0 +1,142 @@
+/*******************************************************************************
+ * Copyright (c) 2013 Ericsson
+ *
+ * All rights reserved. This program and the accompanying materials are
+ * made available under the terms of the Eclipse Public License v1.0 which
+ * accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Marc-Andre Laperle - Initial API and implementation
+ *******************************************************************************/
+
+package org.eclipse.linuxtools.internal.tmf.core.trace.indexer;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.text.MessageFormat;
+
+import org.eclipse.linuxtools.internal.tmf.core.Activator;
+import org.eclipse.linuxtools.tmf.core.timestamp.ITmfTimestamp;
+import org.eclipse.linuxtools.tmf.core.timestamp.TmfTimestamp;
+import org.eclipse.linuxtools.tmf.core.trace.indexer.ITmfPersistentlyIndexable;
+import org.eclipse.linuxtools.tmf.core.trace.indexer.checkpoint.ITmfCheckpoint;
+import org.eclipse.linuxtools.tmf.core.trace.indexer.checkpoint.TmfCheckpoint;
+import org.eclipse.linuxtools.tmf.core.trace.location.ITmfLocation;
+
+/**
+ * An array of checkpoints stored on disk. It is very efficient for searching
+ * checkpoints by rank (O(1))
+ *
+ * @author Marc-Andre Laperle
+ */
+public class FlatArray extends AbstractFileCheckpointCollection {
+    /**
+     * Typical FlatArray file name
+     */
+    public static final String INDEX_FILE_NAME = "checkpoint_flatarray.idx"; //$NON-NLS-1$
+
+    // Cached values
+    private int fCheckpointSize = 0;
+    private ByteBuffer fByteBuffer;
+
+    /**
+     * Constructs a FlatArray for a given trace from scratch or from an existing
+     * file. When the FlatArray is created from scratch, it is populated by
+     * subsequent calls to {@link #insert}.
+     *
+     * @param file
+     *            the file to use as the persistent storage
+     * @param trace
+     *            the trace
+     */
+    public FlatArray(File file, ITmfPersistentlyIndexable trace) {
+        super(file, trace);
+
+        fCheckpointSize = getTrace().getCheckpointSize();
+        fByteBuffer = ByteBuffer.allocate(fCheckpointSize);
+        fByteBuffer.clear();
+    }
+
+    /**
+     * Insert a checkpoint into the file-backed array
+     *
+     * @param checkpoint
+     *            the checkpoint to insert
+     */
+    @Override
+    public void insert(ITmfCheckpoint checkpoint) {
+        try {
+            CheckpointCollectionFileHeader header = getHeader();
+            ++header.fSize;
+            getRandomAccessFile().seek(getRandomAccessFile().length());
+            fByteBuffer.clear();
+            checkpoint.serialize(fByteBuffer);
+            getRandomAccessFile().write(fByteBuffer.array());
+        } catch (IOException e) {
+            Activator.logError(MessageFormat.format(Messages.FlatArray_IOErrorWriting, getFile()), e);
+        }
+    }
+
+    /**
+     * Get a checkpoint from a rank
+     *
+     * @param rank
+     *            the rank to search
+     * @return the checkpoint that has been found or null if not found
+     */
+    public ITmfCheckpoint get(long rank) {
+        ITmfCheckpoint checkpoint = null;
+        try {
+            long pos = getHeader().getSize() + fCheckpointSize * rank;
+            getRandomAccessFile().seek(pos);
+            fByteBuffer.clear();
+            getRandomAccessFile().read(fByteBuffer.array());
+            ITmfLocation location = getTrace().restoreLocation(fByteBuffer);
+            ITmfTimestamp timeStamp = new TmfTimestamp(fByteBuffer);
+            checkpoint = new TmfCheckpoint(timeStamp, location, fByteBuffer);
+        } catch (IOException e) {
+            Activator.logError(MessageFormat.format(Messages.FlatArray_IOErrorReading, getFile()), e);
+        }
+        return checkpoint;
+    }
+
+    /**
+     * Search for a checkpoint and return the rank.
+     *
+     * @param checkpoint
+     *            the checkpoint to search
+     * @return the checkpoint rank of the searched checkpoint, if it is
+     *         contained in the index; otherwise, (-(insertion point) - 1).
+     */
+    @Override
+    public long binarySearch(ITmfCheckpoint checkpoint) {
+        if (getHeader().fSize == 1) {
+            return 0;
+        }
+
+        long lower = 0;
+        long upper = getHeader().fSize - 1;
+        long lastMiddle = -1;
+        long middle = 0;
+        while (lower <= upper && lastMiddle != middle) {
+            lastMiddle = middle;
+            middle = (lower + upper) / 2;
+            ITmfCheckpoint found = get(middle);
+            incCacheMisses();
+            int compare = checkpoint.compareTo(found);
+            if (compare == 0) {
+                return middle;
+            }
+
+            if (compare < 0) {
+                upper = middle;
+            } else {
+                lower = middle + 1;
+            }
+        }
+        long insertionPoint = lower;
+        return -(insertionPoint) - 1;
+    }
+}