/*******************************************************************************
- * Copyright (c) 2009, 2011 Ericsson
+ * Copyright (c) 2009, 2011, 2012 Ericsson
*
* All rights reserved. This program and the accompanying materials are
* made available under the terms of the Eclipse Public License v1.0 which
*
* Contributors:
* Francois Chouinard - Initial API and implementation
+ * Francois Chouinard - Updated as per TMF Trace Model 1.0
*******************************************************************************/
package org.eclipse.linuxtools.tmf.core.trace;
import java.io.FileNotFoundException;
import org.eclipse.core.resources.IProject;
-import org.eclipse.linuxtools.tmf.core.component.ITmfComponent;
-import org.eclipse.linuxtools.tmf.core.event.TmfEvent;
+import org.eclipse.core.resources.IResource;
+import org.eclipse.linuxtools.tmf.core.component.ITmfDataProvider;
+import org.eclipse.linuxtools.tmf.core.event.ITmfEvent;
+import org.eclipse.linuxtools.tmf.core.event.ITmfTimestamp;
import org.eclipse.linuxtools.tmf.core.event.TmfTimeRange;
-import org.eclipse.linuxtools.tmf.core.event.TmfTimestamp;
/**
* <b><u>ITmfTrace</u></b>
* <p>
+ * The event stream structure in TMF. In its basic form, a trace has:
+ * <ul>
+ * <li> the associated Eclipse resource
+ * <li> the path to its location on the file system
+ * <li> the type of the events it contains
+ * <li> the number of events it contains
+ * <li> the time range (span) of the events it contains
+ * </ul>
+ * Concrete ITmfTrace classes have to provide a parameter-less constructor and
+ * an initialization method (initTace())if they are to be opened from the
+ * Project View. Also, a validation (validate()) method has to be provided to
+ * ensure that the trace is of the correct type.
+ * <p>
+ * A trace can be accessed simultaneously from multiple threads by various
+ * application components. To avoid obvious multi-threading issues, the trace
+ * uses an ITmfContext as a synchronization aid for its read operations.
+ * <p>
+ * A proper ITmfContext can be obtained by performing a seek operation on the
+ * trace. Seek operations can be performed for a particular event (by rank or
+ * timestamp) or for a plain trace location.
+ * <p>
+ * <b>Example 1</b>: Read a whole trace
+ * <pre>
+ * ITmfContext context = trace.seekLocationt(null);
+ * ITmfEvent event = trace.getEvent(context);
+ * while (event != null) {
+ * // Do something ...
+ * event = trace.getEvent(context);
+ * }
+ * </pre>
+ * <b>Example 2</b>: Process 50 events starting from the 1000th event
+ * <pre>
+ * int nbEventsRead = 0;
+ * ITmfContext context = trace.seekEvent(1000);
+ * ITmfEvent event = trace.getEvent(context);
+ * while (event != null && nbEventsRead < 50) {
+ * nbEventsRead++;
+ * // Do something ...
+ * event = trace.getEvent(context);
+ * }
+ * </pre>
+ * <b>Example 3</b>: Process the events between 2 timestamps (inclusive)
+ * <pre>
+ * ITmfTimestamp startTime = ...;
+ * ITmfTimestamp endTime = ...;
+ * ITmfContext context = trace.seekEvent(startTime);
+ * ITmfEvent event = trace.getEvent(context);
+ * while (event != null && event.getTimestamp().compareTo(endTime) <= 0) {
+ * // Do something ...
+ * event = trace.getEvent(context);
+ * }
+ * </pre>
*/
-public interface ITmfTrace<T extends TmfEvent> extends ITmfComponent {
-
- // initTrace variants
- public void initTrace(String path, Class<T> eventType) throws FileNotFoundException;
-
- public void initTrace(String path, Class<T> eventType, int cacheSize) throws FileNotFoundException;
-
- public void initTrace(String path, Class<T> eventType, boolean indexTrace) throws FileNotFoundException;
+public interface ITmfTrace<T extends ITmfEvent> extends ITmfDataProvider<T> {
- public void initTrace(String path, Class<T> eventType, int cacheSize, boolean indexTrace) throws FileNotFoundException;
+ // ------------------------------------------------------------------------
+ // Initializers
+ // ------------------------------------------------------------------------
- public void initTrace(String path, Class<T> eventType, int cacheSize, boolean indexTrace, String name) throws FileNotFoundException;
+ /**
+ * Initialize a newly instantiated "empty" trace object. This is used to
+ * properly parameterize an ITmfTrace instantiated with its parameterless
+ * constructor.
+ *
+ * Typically, the parameterless constructor will provide the block size
+ * and its associated parser and indexer.
+ *
+ * @param resource the trace resource
+ * @param path the trace path
+ * @param type the trace event type
+ * @throws FileNotFoundException
+ */
+ public void initTrace(IResource resource, String path, Class<T> type) throws FileNotFoundException;
- // Trace type validation
+ /**
+ * Validate that the trace is of the correct type.
+ *
+ * @param project the eclipse project
+ * @param path the trace path
+ *
+ * @return true if trace is valid
+ */
public boolean validate(IProject project, String path);
- public ITmfTrace<T> copy();
+ // ------------------------------------------------------------------------
+ // Basic getters
+ // ------------------------------------------------------------------------
/**
- * @return the trace path
+ * @return the trace event type
*/
- public String getPath();
+ public Class<T> getType();
/**
- * @return the trace name
+ * @return the associated trace resource
*/
- @Override
- public String getName();
+ public IResource getResource();
/**
- * @return the cache size
+ * @return the trace path
+ */
+ public String getPath();
+
+ /**
+ * @return the trace cache size
*/
public int getCacheSize();
+ // ------------------------------------------------------------------------
+ // Trace characteristics getters
+ // ------------------------------------------------------------------------
+
/**
* @return the number of events in the trace
*/
public long getNbEvents();
/**
- * Trace time range accesses
+ * @return the trace time range
*/
public TmfTimeRange getTimeRange();
- public TmfTimestamp getStartTime();
+ /**
+ * @return the timestamp of the first trace event
+ */
+ public ITmfTimestamp getStartTime();
+
+ /**
+ * @return the timestamp of the last trace event
+ */
+ public ITmfTimestamp getEndTime();
- public TmfTimestamp getEndTime();
+ // ------------------------------------------------------------------------
+ // Trace positioning getters
+ // ------------------------------------------------------------------------
/**
- * @return the streaming interval in ms (0 if not streaming)
+ * @return the current trace location
*/
- public long getStreamingInterval();
+ public ITmfLocation<?> getCurrentLocation();
/**
- * Positions the trace at the first event with the specified timestamp or index (i.e. the nth event in the trace).
- *
- * Returns a context which can later be used to read the event.
+ * Returns the ratio (proportion) corresponding to the specified location.
*
- * @param location
- * @param timestamp
- * @param rank
- * @return a context object for subsequent reads
+ * @param location a trace specific location
+ * @return a floating-point number between 0.0 (beginning) and 1.0 (end)
*/
- public TmfContext seekLocation(ITmfLocation<?> location);
+ public double getLocationRatio(ITmfLocation<?> location);
- public TmfContext seekEvent(TmfTimestamp timestamp);
+ // ------------------------------------------------------------------------
+ // Seek operations (returning a reading context)
+ // ------------------------------------------------------------------------
- public TmfContext seekEvent(long rank);
+ /**
+ * Position the trace at the specified location. The null location
+ * is used to indicate that the first trace event is requested.
+ * <p>
+ * <ul>
+ * <li> a <b>null</b> location returns the context of the first event
+ * <li> an invalid location, including beyond the last event, returns a null context
+ * </ul>
+ * <p>
+ * @param location the trace specific location (null for 1st event)
+ * @return a context which can later be used to read the corresponding event
+ */
+ public ITmfContext seekLocation(ITmfLocation<?> location);
/**
- * Positions the trace at the event located at the specified ratio.
+ * Position the trace at the event located at the specified ratio in the
+ * trace file.
+ * <p>
+ * The notion of ratio (0.0 <= r <= 1.0) is trace specific and left
+ * voluntarily vague. Typically, it would refer to the event proportional
+ * rank (arguably more intuitive) or timestamp in the trace file.
*
- * Returns a context which can later be used to read the event.
+ * @param ratio the proportional 'rank' in the trace
+ * @return a context which can later be used to read the corresponding event
+ */
+ public ITmfContext seekLocation(double ratio);
+
+ /**
+ * Position the trace at the first event with the specified timestamp. If
+ * there is no event with the requested timestamp, a context pointing to
+ * the next chronological event is returned.
+ * <p>
+ * A null timestamp is interpreted as seeking for the first event of the
+ * trace.
+ * <p>
+ * If the requested timestamp is beyond the last trace event, the context
+ * returned will yield a null event if used in a subsequent read.
*
- * @param ratio
- * a floating-point number between 0.0 (beginning) and 1.0 (end)
- * @return a context object for subsequent reads
+ * @param timestamp the timestamp of desired event
+ * @return a context which can later be used to read the corresponding event
*/
- public TmfContext seekLocation(double ratio);
+ public ITmfContext seekEvent(ITmfTimestamp timestamp);
/**
- * Returns the ratio corresponding to the specified location.
+ * Position the trace at the 'rank'th event in the trace.
+ * <p>
+ * If the requested rank is beyond the last trace event, the context
+ * returned will yield a null event if used in a subsequent read.
*
- * @param location
- * a trace location
- * @return a floating-point number between 0.0 (beginning) and 1.0 (end)
+ * @param rank the event rank
+ * @return a context which can later be used to read the corresponding event
*/
- public double getLocationRatio(ITmfLocation<?> location);
+ public ITmfContext seekEvent(long rank);
- public ITmfLocation<?> getCurrentLocation();
+ // ------------------------------------------------------------------------
+ // Read operations (returning an actual event)
+ // ------------------------------------------------------------------------
/**
- * Returns the rank of the first event with the requested timestamp. If none, returns the index of the next event
- * (if any).
+ * Return the event pointed by the supplied context (or null if no event
+ * left) and updates the context to point the next event.
*
- * @param timestamp
- * @return
+ * @param context the read context (will be updated)
+ * @return the event pointed to by the context
*/
- public long getRank(TmfTimestamp timestamp);
+ public ITmfEvent getNextEvent(ITmfContext context);
/**
- * Return the event pointed by the supplied context (or null if no event left) and updates the context to the next
- * event.
+ * Return the event pointed by the supplied context (or null if no event
+ * left) and *does not* update the context.
*
+ * @param context the read context
* @return the next event in the stream
*/
- public TmfEvent getNextEvent(TmfContext context);
+ public ITmfEvent parseEvent(ITmfContext context);
+
+ // ------------------------------------------------------------------------
+ // ------------------------------------------------------------------------
/**
- * Return the event pointed by the supplied context (or null if no event left) and *does not* update the context.
- *
- * @return the next event in the stream
+ * @return the streaming interval in ms (0 if not a streaming trace)
*/
- public TmfEvent parseEvent(TmfContext context);
+ public long getStreamingInterval();
}
projects / deliverable / tracecompass.git / blobdiff