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