001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2009 SonarSource SA
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.api.batch;
021    
022    import org.sonar.api.measures.FormulaData;
023    import org.sonar.api.measures.Measure;
024    import org.sonar.api.measures.Metric;
025    import org.sonar.api.resources.Project;
026    import org.sonar.api.resources.Resource;
027    
028    import java.util.List;
029    
030    /**
031     * A pre-implementation of a decorator using a simple calculation formula
032     * @since 1.11
033     */
034    public class FormulaDecorator implements Decorator {
035    
036      private Metric metric;
037      private DefaultFormulaContext formulaContext;
038    
039      /**
040       * Creates a FormulaDecorator
041       *
042       * @param metric the metric should have an associated formula
043       * 
044       * @throws IllegalArgumentException if no formula is associated to the metric
045       */
046      public FormulaDecorator(Metric metric) {
047        if (metric.getFormula() == null) {
048          throw new IllegalArgumentException("No formula defined on metric");
049        }
050        this.metric = metric;
051        this.formulaContext = new DefaultFormulaContext(metric);
052      }
053    
054      /**
055       * {@inheritDoc}
056       */
057      public boolean shouldExecuteOnProject(Project project) {
058        return true;
059      }
060    
061      /**
062       * @return metric generated by the decorator
063       */
064      @DependedUpon
065      public Metric generatesMetric() {
066        return metric;
067      }
068    
069      /**
070       * @return metric the decorator depends upon
071       */
072      @DependsUpon
073      public List<Metric> dependsUponMetrics() {
074        return metric.getFormula().dependsUponMetrics();
075      }
076    
077      /**
078       * {@inheritDoc}
079       */
080      public void decorate(Resource resource, DecoratorContext context) {
081        if (context.getMeasure(metric) != null) {
082          return;
083        }
084    
085        formulaContext.setDecoratorContext(context);
086        FormulaData data = new DefaultFormulaData(context);
087        Measure measure = metric.getFormula().calculate(data, formulaContext);
088        if (measure != null) {
089          context.saveMeasure(measure);
090        }
091      }
092    
093      @Override
094      public boolean equals(Object o) {
095        if (this == o) {
096          return true;
097        }
098        if (o == null || getClass() != o.getClass()) {
099          return false;
100        }
101    
102        FormulaDecorator that = (FormulaDecorator) o;
103    
104        if (metric != null ? !metric.equals(that.metric) : that.metric != null) {
105          return false;
106        }
107        return true;
108      }
109    
110      @Override
111      public int hashCode() {
112        return metric != null ? metric.hashCode() : 0;
113      }
114    
115      @Override
116      public String toString() {
117        return new StringBuilder().append("f(").append(metric).append(")").toString();
118      }
119    }