analysis/org.eclipse.tracecompass.analysis.lami.ui/src/org/eclipse/tracecompass/internal/provisional/analysis/lami/ui/format/LamiDecimalUnitFormat.java

   1 /*******************************************************************************
   2  * Copyright (c) 2016 EfficiOS Inc., Jonathan Rajotte-Julien
   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
  10 package org.eclipse.tracecompass.internal.provisional.analysis.lami.ui.format;
  11
  12 import java.math.BigDecimal;
  13 import java.text.FieldPosition;
  14
  15 import org.eclipse.jdt.annotation.Nullable;
  16 import org.eclipse.tracecompass.common.core.format.DecimalUnitFormat;
  17 import org.eclipse.tracecompass.internal.provisional.analysis.lami.ui.viewers.LamiGraphRange;
  18
  19 /**
  20  * Decimal formatter for Lami graph
  21  *
  22  * Since the graph use normalized internal value the initial (external)
  23  * representation needs to be obtained. Subsequent formatting is done based on a
  24  * Double. Loss of precision could occurs based on the size. For now, loss of
  25  * precision for decimal values is not a big concern. If it ever become one the
  26  * use of Long while formatting might come in handy.
  27  *
  28  * @author Jonathan Rajotte-Julien
  29  */
  30 public class LamiDecimalUnitFormat extends DecimalUnitFormat {
  31
  32     /** Maximum amount of digits that can be represented into a double */
  33     private static final int BIG_DECIMAL_DIVISION_SCALE = 22;
  34
  35     private static final long serialVersionUID = 977671266270661188L;
  36
  37     private @Nullable LamiGraphRange fInternalRange = null;
  38     private @Nullable LamiGraphRange fExternalRange = null;
  39
  40     /**
  41      * Default constructor
  42      */
  43     public LamiDecimalUnitFormat() {
  44         super();
  45     }
  46
  47     /**
  48      * Constructor with internal and external LamiRange for scale transformation
  49      *
  50      * @param internalRange
  51      *            The internal range used for graph representation
  52      *
  53      * @param externalRange
  54      *            The external (real value) range shown to the user
  55      */
  56     public LamiDecimalUnitFormat(LamiGraphRange internalRange, LamiGraphRange externalRange) {
  57         super();
  58         fInternalRange = internalRange;
  59         fExternalRange = externalRange;
  60     }
  61
  62     /**
  63      * Constructor with multiplication factor.
  64      *
  65      * @param factor
  66      *            Multiplication factor to apply to the value
  67      */
  68     public LamiDecimalUnitFormat(double factor) {
  69         super(factor);
  70     }
  71
  72     /**
  73      * Constructor with multiplication factor and internal and external
  74      * LamiRange for scale transformation.
  75      *
  76      * @param factor
  77      *            Multiplication factor to apply to the value
  78      * @param internalRange
  79      *            The internal range used for graph representation
  80      * @param externalRange
  81      *            The external (real value) range shown to the user
  82      */
  83     public LamiDecimalUnitFormat(double factor, LamiGraphRange internalRange, LamiGraphRange externalRange) {
  84         super(factor);
  85         fInternalRange = internalRange;
  86         fExternalRange = externalRange;
  87     }
  88
  89     /**
  90      * @return the internal range definition
  91      */
  92     public @Nullable LamiGraphRange getInternalRange() {
  93         return fInternalRange;
  94     }
  95
  96     /**
  97      * @param internalRange
  98      *            The internal range definition to be used by the formatter
  99      */
 100     public void setInternalRange(@Nullable LamiGraphRange internalRange) {
 101         fInternalRange = internalRange;
 102     }
 103
 104     /**
 105      * @return the external range definition
 106      */
 107     public @Nullable LamiGraphRange getExternalRange() {
 108         return fExternalRange;
 109     }
 110
 111     /**
 112      * @param externalRange
 113      *            The external range definition to be used by the formatter
 114      */
 115     public void setExternalRange(@Nullable LamiGraphRange externalRange) {
 116         fExternalRange = externalRange;
 117     }
 118
 119     @Override
 120     public StringBuffer format(@Nullable Object obj, @Nullable StringBuffer toAppendTo, @Nullable FieldPosition pos) {
 121         if (!(obj instanceof Number) || toAppendTo == null) {
 122             throw new IllegalArgumentException("Cannot format given Object as a Number: " + obj); //$NON-NLS-1$
 123         }
 124
 125         @Nullable LamiGraphRange internalRange = fInternalRange;
 126         @Nullable LamiGraphRange externalRange = fExternalRange;
 127         if (internalRange == null || externalRange == null) {
 128             StringBuffer buffer = super.format(obj, toAppendTo, pos);
 129             return (buffer == null ? new StringBuffer() : buffer);
 130         }
 131
 132         if (internalRange.getDelta().compareTo(BigDecimal.ZERO) == 0) {
 133             StringBuffer buffer = super.format(externalRange.getMinimum().doubleValue(), toAppendTo, pos);
 134             return (buffer == null ? new StringBuffer() : buffer);
 135         }
 136
 137         if (externalRange.getDelta().compareTo(BigDecimal.ZERO) == 0) {
 138             StringBuffer buffer = super.format(externalRange.getMinimum().doubleValue(), toAppendTo, pos);
 139             return (buffer == null ? new StringBuffer() : buffer);
 140         }
 141
 142         /* Find external value before formatting */
 143         BigDecimal externalValue = (new BigDecimal(obj.toString()))
 144                 .subtract(internalRange.getMinimum())
 145                 .multiply(externalRange.getDelta())
 146                 .divide(internalRange.getDelta(), BIG_DECIMAL_DIVISION_SCALE, BigDecimal.ROUND_DOWN)
 147                 .add(externalRange.getMinimum());
 148
 149         Double value = externalValue.doubleValue();
 150         StringBuffer buffer = super.format(value, toAppendTo, pos);
 151         return (buffer == null ? new StringBuffer() : buffer);
 152     }
 153 }