### Question:
ChgrpBuilder extends ChFSBaseBuilder<ChgrpBuilder> implements Builder<Chgrp> { public ChgrpBuilder withGroup(final String group) { this.group.set(group); return this; } ChgrpBuilder(); ChgrpBuilder withGroup(final String group); @Override Chgrp build();  }### Answer:
@Test public void testWithGroup() { final String group = "root"; final ChgrpBuilder builder = new ChgrpBuilder(); builder.withGroup(group); final Chgrp chgrp = builder.build(); assertEquals(group, chgrp.getGroup()); }
@Test public void testWithPermissionsCalledTwiceThrows() { final String group1 = "group1"; final String group2 = "group1"; final ChgrpBuilder builder = new ChgrpBuilder(); builder.withGroup(group1); expectedException.expect(IllegalStateException.class); builder.withGroup(group2); }