### Question:
ImmutableNamespaces implements Namespaces { @Override public String toString() { StringBuilder builder=new StringBuilder(); builder.append("Namespaces {"); for(Entry<String,String> entry:this.map.entrySet()) { String namespaceURI = entry.getValue(); String prefix = entry.getKey(); String line=String.format(" - \"%s\" : \"%s\" [%s]",prefix,namespaceURI,namespaceURI.getClass().getName()); builder.append(LINE_SEPARATOR).append(line); } if(!this.map.isEmpty()) { builder.append(LINE_SEPARATOR); } builder.append("}"); return builder.toString(); } 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 testToString$empty() throws Exception { final ImmutableNamespaces ns = new ImmutableNamespaces(); assertThat(ns.toString(),not(equalTo(Utils.defaultToString(ns)))); }
@Test public void testToString$nonEmpty() throws Exception { assertThat(this.sut.toString(),not(equalTo(Utils.defaultToString(this.sut)))); }