### Question:
ImmutableNamespaces implements Namespaces { @Override public String getNamespaceURI(String prefix) { return this.map.get(prefix); } private  ImmutableNamespaces(Map<String,String> map);  ImmutableNamespaces(); ImmutableNamespaces withPrefix(String prefix, String namespaceURI); ImmutableNamespaces withoutPrefix(String... prefixes); @Override Set<String> getDeclaredPrefixes(); @Override String getNamespaceURI(String prefix); @Override String getPrefix(String namespaceURI); @Override List<String> getPrefixes(String namespaceURI); @Override String toString();  }### Answer:
@Test public void testGetNamespaceURI() throws Exception { assertThat(this.sut.getNamespaceURI(DEFAULT_PR1),equalTo(DEFAULT_NAMESPACE)); assertThat(this.sut.getNamespaceURI(DEFAULT_PR2),equalTo(DEFAULT_NAMESPACE)); }