org.eclipse.linuxtools.tmf.core/src/org/eclipse/linuxtools/tmf/core/statesystem/ITmfStateSystem.java

   1 /*******************************************************************************
   2  * Copyright (c) 2012 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Alexandre Montplaisir - Initial API
  11  ******************************************************************************/
  12
  13 package org.eclipse.linuxtools.tmf.core.statesystem;
  14
  15 import java.util.List;
  16
  17 import org.eclipse.core.runtime.IProgressMonitor;
  18 import org.eclipse.linuxtools.tmf.core.exceptions.AttributeNotFoundException;
  19 import org.eclipse.linuxtools.tmf.core.exceptions.StateValueTypeException;
  20 import org.eclipse.linuxtools.tmf.core.exceptions.TimeRangeException;
  21 import org.eclipse.linuxtools.tmf.core.interval.ITmfStateInterval;
  22 import org.eclipse.linuxtools.tmf.core.statevalue.ITmfStateValue;
  23
  24 /**
  25  * This is the read-only interface to the generic state system. It contains all
  26  * the read-only quark-getting methods, as well as the history-querying ones.
  27  *
  28  * @author Alexandre Montplaisir
  29  * @version 2.0
  30  * @since 2.0
  31  */
  32 public interface ITmfStateSystem {
  33
  34     /**
  35      * Return the start time of this history. It usually matches the start time
  36      * of the original trace.
  37      *
  38      * @return The history's registered start time
  39      */
  40     public long getStartTime();
  41
  42     /**
  43      * Return the current end time of the history.
  44      *
  45      * @return The current end time of this state history
  46      */
  47     public long getCurrentEndTime();
  48
  49     /**
  50      * Return the current total amount of attributes in the system. This is also
  51      * equal to the quark that will be assigned to the next attribute that's
  52      * created.
  53      *
  54      * @return The current number of attributes in the system
  55      */
  56     public int getNbAttributes();
  57
  58     /**
  59      * Check if a given quark is the last attribute that was added to the
  60      * system.
  61      *
  62      * This is a common case, and it's a bit clearer than
  63      * " x == getNbAttributes - 1"
  64      *
  65      * @param quark
  66      *            The quark to check for
  67      * @return True if this is the last quark that was added to the system,
  68      *         false if not
  69      * @since 2.0
  70      */
  71     public boolean isLastAttribute(int quark);
  72
  73     /**
  74      * @name Read-only quark-getting methods
  75      */
  76
  77     /**
  78      * Basic quark-retrieving method. Pass an attribute in parameter as an array
  79      * of strings, the matching quark will be returned.
  80      *
  81      * This version will NOT create any new attributes. If an invalid attribute
  82      * is requested, an exception will be thrown.
  83      *
  84      * @param attribute
  85      *            Attribute given as its full path in the Attribute Tree
  86      * @return The quark of the requested attribute, if it existed.
  87      * @throws AttributeNotFoundException
  88      *             This exception is thrown if the requested attribute simply
  89      *             did not exist in the system.
  90      */
  91     public int getQuarkAbsolute(String... attribute)
  92             throws AttributeNotFoundException;
  93
  94     /**
  95      * "Relative path" quark-getting method. Instead of specifying a full path,
  96      * if you know the path is relative to another attribute for which you
  97      * already have the quark, use this for better performance.
  98      *
  99      * This is useful for cases where a lot of modifications or queries will
 100      * originate from the same branch of the attribute tree : the common part of
 101      * the path won't have to be re-hashed for every access.
 102      *
 103      * This version will NOT create any new attributes. If an invalid attribute
 104      * is requested, an exception will be thrown.
 105      *
 106      * @param startingNodeQuark
 107      *            The quark of the attribute from which 'subPath' originates.
 108      * @param subPath
 109      *            "Rest" of the path to get to the final attribute
 110      * @return The matching quark, if it existed
 111      * @throws AttributeNotFoundException
 112      *             If the quark is invalid
 113      */
 114     public int getQuarkRelative(int startingNodeQuark, String... subPath)
 115             throws AttributeNotFoundException;
 116
 117     /**
 118      * Return the sub-attributes of the target attribute, as a List of quarks.
 119      *
 120      * @param quark
 121      *            The attribute of which you want to sub-attributes. You can use
 122      *            "-1" here to specify the root node.
 123      * @param recursive
 124      *            True if you want all recursive sub-attributes, false if you
 125      *            only want the first level.
 126      * @return A List of integers, matching the quarks of the sub-attributes.
 127      * @throws AttributeNotFoundException
 128      *             If the quark was not existing or invalid.
 129      */
 130     public List<Integer> getSubAttributes(int quark, boolean recursive)
 131             throws AttributeNotFoundException;
 132
 133     /**
 134      * Batch quark-retrieving method. This method allows you to specify a path
 135      * pattern which includes a wildcard "*" somewhere. It will check all the
 136      * existing attributes in the attribute tree and return those who match the
 137      * pattern.
 138      *
 139      * For example, passing ("Threads", "*", "Exec_mode") will return the list
 140      * of quarks for attributes "Threads/1000/Exec_mode",
 141      * "Threads/1500/Exec_mode", and so on, depending on what exists at this
 142      * time in the attribute tree.
 143      *
 144      * If no wildcard is specified, the behavior is the same as
 145      * getQuarkAbsolute() (except it will return a List with one entry). This
 146      * method will never create new attributes.
 147      *
 148      * Only one wildcard "*" is supported at this time.
 149      *
 150      * @param pattern
 151      *            The array of strings representing the pattern to look for. It
 152      *            should ideally contain one entry that is only a "*".
 153      * @return A List of attribute quarks, representing attributes that matched
 154      *         the pattern. If no attribute matched, the list will be empty (but
 155      *         not null).
 156      */
 157     public List<Integer> getQuarks(String... pattern);
 158
 159     /**
 160      * Return the name assigned to this quark. This returns only the "basename",
 161      * not the complete path to this attribute.
 162      *
 163      * @param attributeQuark
 164      *            The quark for which we want the name
 165      * @return The name of the quark
 166      */
 167     public String getAttributeName(int attributeQuark);
 168
 169     /**
 170      * This returns the slash-separated path of an attribute by providing its
 171      * quark
 172      *
 173      * @param attributeQuark
 174      *            The quark of the attribute we want
 175      * @return One single string separated with '/', like a filesystem path
 176      */
 177     public String getFullAttributePath(int attributeQuark);
 178
 179     /**
 180      * @name Query methods
 181      */
 182
 183     /**
 184      * Returns the current state value we have (in the Transient State) for the
 185      * given attribute.
 186      *
 187      * This is useful even for a StateHistorySystem, as we are guaranteed it
 188      * will only do a memory access and not go look on disk (and we don't even
 189      * have to provide a timestamp!)
 190      *
 191      * @param attributeQuark
 192      *            For which attribute we want the current state
 193      * @return The State value that's "current" for this attribute
 194      * @throws AttributeNotFoundException
 195      *             If the requested attribute is invalid
 196      */
 197     public ITmfStateValue queryOngoingState(int attributeQuark)
 198             throws AttributeNotFoundException;
 199
 200     /**
 201      * Load the complete state information at time 't' into the returned List.
 202      * You can then get the intervals for single attributes by using
 203      * List.get(n), where 'n' is the quark of the attribute.
 204      *
 205      * On average if you need around 10 or more queries for the same timestamps,
 206      * use this method. If you need less than 10 (for example, running many
 207      * queries for the same attributes but at different timestamps), you might
 208      * be better using the querySingleState() methods instead.
 209      *
 210      * @param t
 211      *            We will recreate the state information to what it was at time
 212      *            t.
 213      * @return The List of intervals, where the offset = the quark
 214      * @throws TimeRangeException
 215      *             If the 't' parameter is outside of the range of the state
 216      *             history.
 217      */
 218     public List<ITmfStateInterval> queryFullState(long t)
 219             throws TimeRangeException;
 220
 221     /**
 222      * Singular query method. This one does not update the whole stateInfo
 223      * vector, like queryFullState() does. It only searches for one specific
 224      * entry in the state history.
 225      *
 226      * It should be used when you only want very few entries, instead of the
 227      * whole state (or many entries, but all at different timestamps). If you do
 228      * request many entries all at the same time, you should use the
 229      * conventional queryFullState() + List.get() method.
 230      *
 231      * @param t
 232      *            The timestamp at which we want the state
 233      * @param attributeQuark
 234      *            Which attribute we want to get the state of
 235      * @return The StateInterval representing the state
 236      * @throws TimeRangeException
 237      *             If 't' is invalid
 238      * @throws AttributeNotFoundException
 239      *             If the requested quark does not exist in the model
 240      */
 241     public ITmfStateInterval querySingleState(long t, int attributeQuark)
 242             throws AttributeNotFoundException, TimeRangeException;
 243
 244     /**
 245      * Convenience method to query attribute stacks (created with
 246      * pushAttribute()/popAttribute()). This will return the interval that is
 247      * currently at the top of the stack, or 'null' if that stack is currently
 248      * empty. It works similarly to querySingleState().
 249      *
 250      * To retrieve the other values in a stack, you can query the sub-attributes
 251      * manually.
 252      *
 253      * @param t
 254      *            The timestamp of the query
 255      * @param stackAttributeQuark
 256      *            The top-level stack-attribute (that was the target of
 257      *            pushAttribute() at creation time)
 258      * @return The interval that was at the top of the stack, or 'null' if the
 259      *         stack was empty.
 260      * @throws StateValueTypeException
 261      *             If the target attribute is not a valid stack attribute (if it
 262      *             has a string value for example)
 263      * @throws AttributeNotFoundException
 264      *             If the attribute was simply not found
 265      * @throws TimeRangeException
 266      *             If the given timestamp is invalid
 267      * @since 2.0
 268      */
 269     public ITmfStateInterval querySingleStackTop(long t, int stackAttributeQuark)
 270             throws StateValueTypeException, AttributeNotFoundException,
 271             TimeRangeException;
 272
 273     /**
 274      * Return a list of state intervals, containing the "history" of a given
 275      * attribute between timestamps t1 and t2. The list will be ordered by
 276      * ascending time.
 277      *
 278      * Note that contrary to queryFullState(), the returned list here is in the
 279      * "direction" of time (and not in the direction of attributes, as is the
 280      * case with queryFullState()).
 281      *
 282      * @param attributeQuark
 283      *            Which attribute this query is interested in
 284      * @param t1
 285      *            Start time of the range query
 286      * @param t2
 287      *            Target end time of the query. If t2 is greater than the end of
 288      *            the trace, we will return what we have up to the end of the
 289      *            history.
 290      * @return The List of state intervals that happened between t1 and t2
 291      * @throws TimeRangeException
 292      *             If t1 is invalid, or if t2 <= t1
 293      * @throws AttributeNotFoundException
 294      *             If the requested quark does not exist in the model.
 295      */
 296     public List<ITmfStateInterval> queryHistoryRange(int attributeQuark,
 297             long t1, long t2) throws TimeRangeException,
 298             AttributeNotFoundException;
 299
 300     /**
 301      * Return the state history of a given attribute, but with at most one
 302      * update per "resolution". This can be useful for populating views (where
 303      * it's useless to have more than one query per pixel, for example). A
 304      * progress monitor can be used to cancel the query before completion.
 305      *
 306      * @param attributeQuark
 307      *            Which attribute this query is interested in
 308      * @param t1
 309      *            Start time of the range query
 310      * @param t2
 311      *            Target end time of the query. If t2 is greater than the end of
 312      *            the trace, we will return what we have up to the end of the
 313      *            history.
 314      * @param resolution
 315      *            The "step" of this query
 316      * @param monitor
 317      *            A progress monitor. If the monitor is canceled during a query,
 318      *            we will return what has been found up to that point. You can
 319      *            use "null" if you do not want to use one.
 320      * @return The List of states that happened between t1 and t2
 321      * @throws TimeRangeException
 322      *             If t1 is invalid, if t2 <= t1, or if the resolution isn't
 323      *             greater than zero.
 324      * @throws AttributeNotFoundException
 325      *             If the attribute doesn't exist
 326      * @since 2.0
 327      */
 328     public List<ITmfStateInterval> queryHistoryRange(int attributeQuark,
 329             long t1, long t2, long resolution, IProgressMonitor monitor)
 330             throws TimeRangeException, AttributeNotFoundException;
 331 }