1 /*
2  * Copyright (C) 2015 The Android Open Source Project
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 
17 package com.android.inputmethod.latin.common;
18 
19 /**
20  * Emojis are supplementary characters expressed as a low+high pair. For instance,
21  * the emoji U+1F625 is encoded as "\uD83D\uDE25" in UTF-16, where '\uD83D' is in
22  * the range of [0xd800, 0xdbff] and '\uDE25' is in the range of [0xdc00, 0xdfff].
23  * {@see http://docs.oracle.com/javase/6/docs/api/java/lang/Character.html#unicode}
24  */
25 public final class UnicodeSurrogate {
26     private static final char LOW_SURROGATE_MIN = '\uD800';
27     private static final char LOW_SURROGATE_MAX = '\uDBFF';
28     private static final char HIGH_SURROGATE_MIN = '\uDC00';
29     private static final char HIGH_SURROGATE_MAX = '\uDFFF';
30 
isLowSurrogate(final char c)31     public static boolean isLowSurrogate(final char c) {
32         return c >= LOW_SURROGATE_MIN && c <= LOW_SURROGATE_MAX;
33     }
34 
isHighSurrogate(final char c)35     public static boolean isHighSurrogate(final char c) {
36         return c >= HIGH_SURROGATE_MIN && c <= HIGH_SURROGATE_MAX;
37     }
38 }
39