### Question:
SequencerConfig extends ComponentConfig { static Set<SequencerPathExpression> buildPathExpressionSet( String... pathExpressions ) { Set<SequencerPathExpression> result = null; if (pathExpressions != null) { result = new LinkedHashSet<SequencerPathExpression>(); for (String pathExpression : pathExpressions) { if (pathExpression == null) continue; pathExpression = pathExpression.trim(); if (pathExpression.length() == 0) continue; result.add(SequencerPathExpression.compile(pathExpression)); } result = Collections.unmodifiableSet(result); } else { result = Collections.emptySet(); } return result; } SequencerConfig( String name,
                            String description,
                            String classname,
                            String[] classpath,
                            String... pathExpressions );  SequencerConfig( String name,
                            String description,
                            Map<String, Object> properties,
                            String classname,
                            String[] classpath,
                            String... pathExpressions );  SequencerConfig( String name,
                            String description,
                            long timestamp,
                            Map<String, Object> properties,
                            String classname,
                            String[] classpath,
                            String... pathExpressions ); Collection<SequencerPathExpression> getPathExpressions(); boolean hasChanged( SequencerConfig that ); static final String REPLACE_PREVIOUSLY_DERIVED_CONTENT_PROPERTY_NAME; static final String DEFAULT_REPLACE_PREVIOUSLY_DERIVED_CONTENT_PROPERTY_VALUE; }### Answer:
@Test public void shouldNotAddNullOrBlankPathExpressions() { assertThat(SequencerConfig.buildPathExpressionSet(null, "", " ", validPathExpressions[0]).size(), is(1)); }
@Test public void shouldNotAddSamePathExpressionMoreThanOnce() { assertThat(SequencerConfig.buildPathExpressionSet(validPathExpressions[0], validPathExpressions[0], validPathExpressions[0]).size(), is(1)); }