sourcePaths.add(sourcePath);
    }

    public void addSourcePaths(Set<String> sourcePath) {
        sourcePaths.addAll(sourcePath);
    }

    public Collection<String> getSourcePaths() {
        return Collections.unmodifiableCollection(sourcePaths);
    }

    public boolean isBuildNeeded() {
        return isFullRebuildNeeded() || !classesToCompile.isEmpty() || !classesToProcess.isEmpty();
    }

        PatternSet classesToDelete = fileOperations.patternSet();
        PatternSet sourceToCompile = fileOperations.patternSet();

        prepareFilePatterns(recompilationSpec.getClassesToCompile(), recompilationSpec.getSourcePaths(), classesToDelete, sourceToCompile);
        spec.setSourceFiles(narrowDownSourcesToCompile(sourceTree, sourceToCompile));
        includePreviousCompilationOutputOnClasspath(spec);

    }

    @Override
    public void addChildSpecListener(CopySpecListener copySpecListener) {
        this.listeners.add(copySpecListener);
    }

    @VisibleForTesting
    public Set<Object> getSourcePaths() {
        return sourcePaths.getFrom();
    }

    @Nullable
    public String getDestPath() {
        return destDir == null ? null : PATH_NOTATION_PARSER.parseNotation(destDir);
    }