1   /**
2    * Copyright 2014 Netflix, Inc.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    * http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package rx.internal.operators;
17  
18  import rx.Observable.Operator;
19  import rx.Subscriber;
20  import rx.functions.Func1;
21  import rx.functions.Func2;
22  
23  /**
24   * Skips any emitted source items as long as the specified condition holds true. Emits all further source items
25   * as soon as the condition becomes false.
26   */
27  public final class OperatorSkipWhile<T> implements Operator<T, T> {
28      private final Func2<? super T, Integer, Boolean> predicate;
29  
30      public OperatorSkipWhile(Func2<? super T, Integer, Boolean> predicate) {
31          this.predicate = predicate;
32      }
33      @Override
34      public Subscriber<? super T> call(final Subscriber<? super T> child) {
35          return new Subscriber<T>(child) {
36              boolean skipping = true;
37              int index;
38              @Override
39              public void onNext(T t) {
40                  if (!skipping) {
41                      child.onNext(t);
42                  } else {
43                      if (!predicate.call(t, index++)) {
44                          skipping = false;
45                          child.onNext(t);
46                      } else {
47                          request(1);
48                      }
49                  }
50              }
51  
52              @Override
53              public void onError(Throwable e) {
54                  child.onError(e);
55              }
56  
57              @Override
58              public void onCompleted() {
59                  child.onCompleted();
60              }
61          };
62      }
63      /** Convert to Func2 type predicate. */
64      public static <T> Func2<T, Integer, Boolean> toPredicate2(final Func1<? super T, Boolean> predicate) {
65          return new Func2<T, Integer, Boolean>() {
66  
67              @Override
68              public Boolean call(T t1, Integer t2) {
69                  return predicate.call(t1);
70              }
71          };
72      }
73  }