1 files changed, 209 insertions, 0 deletions
diff --git a/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/synchronization/TimestampTransformFactory.java b/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/synchronization/TimestampTransformFactory.java
new file mode 100644
index 0000000000..ddb0a505ac
--- /dev/null
+++ b/tmf/org.eclipse.tracecompass.tmf.core/src/org/eclipse/tracecompass/tmf/core/synchronization/TimestampTransformFactory.java
@@ -0,0 +1,209 @@
+/*******************************************************************************
+ * Copyright (c) 2014 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:
+ *   Matthew Khouzam - Initial implementation and API
+ *******************************************************************************/
+package org.eclipse.tracecompass.tmf.core.synchronization;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.math.BigDecimal;
+
+import org.eclipse.core.resources.IResource;
+import org.eclipse.core.runtime.CoreException;
+import org.eclipse.jdt.annotation.NonNullByDefault;
+import org.eclipse.jdt.annotation.Nullable;
+import org.eclipse.tracecompass.common.core.NonNullUtils;
+import org.eclipse.tracecompass.internal.tmf.core.Activator;
+import org.eclipse.tracecompass.internal.tmf.core.synchronization.TmfConstantTransform;
+import org.eclipse.tracecompass.internal.tmf.core.synchronization.TmfTimestampTransform;
+import org.eclipse.tracecompass.internal.tmf.core.synchronization.TmfTimestampTransformLinearFast;
+import org.eclipse.tracecompass.tmf.core.TmfCommonConstants;
+import org.eclipse.tracecompass.tmf.core.timestamp.ITmfTimestamp;
+
+/**
+ * A factory to generate timestamp tranforms
+ *
+ * @author Matthew Khouzam
+ */
+@NonNullByDefault
+public final class TimestampTransformFactory {
+
+    private static final String SYNCHRONIZATION_FORMULA_FILE = "sync_formula"; //$NON-NLS-1$
+
+    private TimestampTransformFactory() {
+    }
+
+    /**
+     * Creates the identity timestamp transform
+     *
+     * @return The identity timestamp transform
+     */
+    public static ITmfTimestampTransform getDefaultTransform() {
+        return TmfTimestampTransform.IDENTITY;
+    }
+
+    /**
+     * Create an offsetted transform
+     *
+     * @param offset
+     *            the offset in long format, nanosecond scale
+     * @return the offsetted transform
+     */
+    public static ITmfTimestampTransform createWithOffset(long offset) {
+        if (offset == 0) {
+            return TmfTimestampTransform.IDENTITY;
+        }
+        return new TmfConstantTransform(offset);
+    }
+
+    /**
+     * Create an offsetted transform
+     *
+     * @param offset
+     *            the offset in a timestamp with scale
+     * @return the offsetted transform
+     */
+    public static ITmfTimestampTransform createWithOffset(ITmfTimestamp offset) {
+        if (offset.getValue() == 0) {
+            return TmfTimestampTransform.IDENTITY;
+        }
+        return new TmfConstantTransform(offset);
+    }
+
+    /**
+     * Create a timestamp transform corresponding to a linear equation, with
+     * slope and offset. The expected timestamp transform is such that f(t) =
+     * m*x + b, where m is the slope and b the offset.
+     *
+     * @param factor
+     *            the slope
+     * @param offset
+     *            the offset
+     * @return the transform
+     */
+    public static ITmfTimestampTransform createLinear(double factor, ITmfTimestamp offset) {
+        if (factor == 1.0) {
+            return createWithOffset(offset);
+        }
+        return new TmfTimestampTransformLinearFast(factor, offset.normalize(0, ITmfTimestamp.NANOSECOND_SCALE).getValue());
+    }
+
+    /**
+     * Create a timestamp transform corresponding to a linear equation, with
+     * slope and offset. The expected timestamp transform is such that f(t) =
+     * m*x + b, where m is the slope and b the offset.
+     *
+     * @param factor
+     *            the slope
+     * @param offset
+     *            the offset in nanoseconds
+     * @return the transform
+     */
+    public static ITmfTimestampTransform createLinear(double factor, long offset) {
+        if (factor == 1.0) {
+            return createWithOffset(offset);
+        }
+        return new TmfTimestampTransformLinearFast(factor, offset);
+    }
+
+    /**
+     * Create a timestamp transform corresponding to a linear equation, with
+     * slope and offset expressed in BigDecimal. The expected timestamp
+     * transform is such that f(t) = m*x + b, where m is the slope and b the
+     * offset.
+     *
+     * @param factor
+     *            the slope
+     * @param offset
+     *            the offset in nanoseconds
+     * @return the transform
+     */
+    public static ITmfTimestampTransform createLinear(BigDecimal factor, BigDecimal offset) {
+        if (factor.equals(BigDecimal.ONE)) {
+            return createWithOffset(offset.longValueExact());
+        }
+        return new TmfTimestampTransformLinearFast(factor, offset);
+    }
+
+    /**
+     * Returns the file resource used to store synchronization formula. The file
+     * may not exist.
+     *
+     * @param resource
+     *            the trace resource
+     * @return the synchronization file
+     */
+    private static @Nullable File getSyncFormulaFile(@Nullable IResource resource) {
+        if (resource == null) {
+            return null;
+        }
+        try {
+            String supplDirectory = resource.getPersistentProperty(TmfCommonConstants.TRACE_SUPPLEMENTARY_FOLDER);
+            return new File(supplDirectory + File.separator + SYNCHRONIZATION_FORMULA_FILE);
+        } catch (CoreException e) {
+            /* Ignored */
+        }
+        return null;
+    }
+
+    /**
+     * Returns the timestamp transform for a trace resource
+     *
+     * @param resource
+     *            the trace resource
+     * @return the timestamp transform
+     */
+    public static ITmfTimestampTransform getTimestampTransform(@Nullable IResource resource) {
+        File syncFile = getSyncFormulaFile(resource);
+        if (syncFile != null && syncFile.exists()) {
+            /* Read the serialized object from file */
+            try (FileInputStream fis = new FileInputStream(syncFile);
+                    ObjectInputStream ois = new ObjectInputStream(fis);) {
+                return NonNullUtils.checkNotNull((ITmfTimestampTransform) ois.readObject());
+            } catch (ClassNotFoundException | IOException e) {
+            }
+        }
+        return TimestampTransformFactory.getDefaultTransform();
+    }
+
+    /**
+     * Sets the trace resource's timestamp transform
+     *
+     * @param resource
+     *            the trace resource
+     * @param tt
+     *            The timestamp transform for all timestamps of this trace, or
+     *            null to clear it
+     */
+    public static void setTimestampTransform(@Nullable IResource resource, @Nullable ITmfTimestampTransform tt) {
+        /* Save the timestamp transform to a file */
+        File syncFile = getSyncFormulaFile(resource);
+        if (syncFile != null) {
+            if (syncFile.exists()) {
+                syncFile.delete();
+            }
+            if (tt == null) {
+                return;
+            }
+            /* Write the serialized object to file */
+            try (FileOutputStream fos = new FileOutputStream(syncFile, false);
+                    ObjectOutputStream oos = new ObjectOutputStream(fos);) {
+                oos.writeObject(tt);
+            } catch (IOException e1) {
+                Activator.logError("Error writing timestamp transform for trace", e1); //$NON-NLS-1$
+            }
+        }
+    }
+
+}