### Question:
StreamingBuilder implements Builder<Streaming> { public StreamingBuilder withEnv(final String env) { this.envs.add(env); return this; } StreamingBuilder(); StreamingBuilder withMapper(final String mapper); StreamingBuilder withReducer(final String reducer); StreamingBuilder withRecordReader(final String recordReader); StreamingBuilder withRecordReaderMapping(final String recordReaderMapping); StreamingBuilder withEnv(final String env); @Override Streaming build();  }### Answer:
@Test public void testWithEnv() { final String env1 = "env1"; final String env2 = "env2"; final StreamingBuilder builder = new StreamingBuilder(); builder.withEnv(env1) .withEnv(env2); final Streaming streaming = builder.build(); assertEquals(Arrays.asList(env1, env2), streaming.getEnvs()); }