org.eclipse.tracecompass.tmf.ui/src/org/eclipse/tracecompass/tmf/ui/viewers/events/columns/TmfEventTableColumn.java

   1 /*******************************************************************************
   2  * Copyright (c) 2014 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 and implementation
  11  ******************************************************************************/
  12
  13 package org.eclipse.tracecompass.tmf.ui.viewers.events.columns;
  14
  15 import org.eclipse.jdt.annotation.NonNullByDefault;
  16 import org.eclipse.jdt.annotation.Nullable;
  17 import org.eclipse.tracecompass.internal.tmf.ui.viewers.events.columns.TmfContentsColumn;
  18 import org.eclipse.tracecompass.internal.tmf.ui.viewers.events.columns.TmfTimestampColumn;
  19 import org.eclipse.tracecompass.internal.tmf.ui.viewers.events.columns.TmfTypeColumn;
  20 import org.eclipse.tracecompass.tmf.core.event.ITmfEvent;
  21
  22 /**
  23  * A column in the
  24  * {@link org.eclipse.tracecompass.tmf.ui.viewers.events.TmfEventsTable}. In
  25  * addition to ones provided by default, trace types can extend this class to
  26  * create additional columns specific to their events.
  27  *
  28  * Those additional columns can then be passed to the constructor
  29  * {@link org.eclipse.tracecompass.tmf.ui.viewers.events.TmfEventsTable#TmfEventsTable(org.eclipse.swt.widgets.Composite, int, java.util.Collection)}
  30  *
  31  * @author Alexandre Montplaisir
  32  * @since 3.1
  33  */
  34 @NonNullByDefault
  35 public abstract class TmfEventTableColumn {
  36
  37     // ------------------------------------------------------------------------
  38     // Class attributes
  39     // ------------------------------------------------------------------------
  40
  41     /**
  42      * The base set of columns, which can apply to any trace type.
  43      */
  44     public static interface BaseColumns {
  45
  46         /** Column showing the event timestamp */
  47         TmfEventTableColumn TIMESTAMP = new TmfTimestampColumn();
  48
  49         /** Column showing the event type */
  50         TmfEventTableColumn EVENT_TYPE = new TmfTypeColumn();
  51
  52         /** Column showing the aggregated event contents (fields) */
  53         TmfEventTableColumn CONTENTS = new TmfContentsColumn();
  54     }
  55
  56     /**
  57      * Static definition of an empty string. Return this instead of returning
  58      * 'null'!
  59      */
  60     protected static final String EMPTY_STRING = ""; //$NON-NLS-1$
  61
  62     // ------------------------------------------------------------------------
  63     // Fields
  64     // ------------------------------------------------------------------------
  65
  66     private final String fHeaderName;
  67     private final @Nullable String fHeaderTooltip;
  68
  69     // ------------------------------------------------------------------------
  70     // Constructors
  71     // ------------------------------------------------------------------------
  72
  73     /**
  74      * Constructor with no tooltip.
  75      *
  76      * @param headerName
  77      *            The name (title) of this column. Should ideally be short.
  78      */
  79     public TmfEventTableColumn(String headerName) {
  80         fHeaderName = headerName;
  81         fHeaderTooltip = null;
  82     }
  83
  84     /**
  85      * Constructor with a tooltip.
  86      *
  87      * @param headerName
  88      *            The name (title) of this column. Should ideally be short.
  89      * @param headerTooltip
  90      *            The tooltip text for the column header. Use 'null' for no
  91      *            tooltip.
  92      */
  93     public TmfEventTableColumn(String headerName, @Nullable String headerTooltip) {
  94         fHeaderName = headerName;
  95         fHeaderTooltip = headerTooltip;
  96     }
  97
  98     // ------------------------------------------------------------------------
  99     // Getters
 100     // ------------------------------------------------------------------------
 101
 102     /**
 103      * Get this column's header name, a.k.a. title
 104      *
 105      * @return The column's title
 106      */
 107     public String getHeaderName() {
 108         return fHeaderName;
 109     }
 110
 111     /**
 112      * Get the tooltip text for the column header
 113      *
 114      * @return The header's tooltip
 115      */
 116     public @Nullable String getHeaderTooltip() {
 117         return fHeaderTooltip;
 118     }
 119
 120     // ------------------------------------------------------------------------
 121     // Abstract methods
 122     // ------------------------------------------------------------------------
 123
 124     /**
 125      * Get the string that should be displayed in this column's cell for a given
 126      * trace event. Basically, this defines "what to print in this column for
 127      * this event".
 128      * <p>
 129      * Note to implementers:
 130      * <p>
 131      * This method takes an {@link ITmfEvent}, because any type of event could
 132      * potentially be present in the table at the time. Do not assume that you
 133      * will only receive events of your trace type. You'd probably want to
 134      * return an empty string for event that don't match your expected class
 135      * type here.
 136      *
 137      * @param event
 138      *            The trace event whose element we want to display
 139      * @return The string to display in the column for this event
 140      */
 141     public abstract String getItemString(ITmfEvent event);
 142
 143     /**
 144      * Return the FILTER_ID used by the filters to search this column.
 145      *
 146      * @return The filter ID for this column, or 'null' to not provide a filter
 147      *         ID (which will mean this column will probably not be
 148      *         searchable/filterable.)
 149      */
 150     public abstract @Nullable String getFilterFieldId();
 151 }