1/*
2 * Copyright (C) 2010 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#ifndef SCOPED_JAVA_UNICODE_STRING_H_included
18#define SCOPED_JAVA_UNICODE_STRING_H_included
19
20#include "JNIHelp.h"
21#include "unicode/unistr.h"
22
23// A smart pointer that provides access to an ICU UnicodeString given a JNI
24// jstring. We give ICU a direct pointer to the characters on the Java heap.
25// It's clever enough to copy-on-write if necessary.
26class ScopedJavaUnicodeString {
27 public:
28  ScopedJavaUnicodeString(JNIEnv* env, jstring s) : mEnv(env), mString(s) {
29    if (s == NULL) {
30      jniThrowNullPointerException(mEnv, NULL);
31    } else {
32      mChars = env->GetStringChars(mString, NULL);
33      const int32_t charCount = env->GetStringLength(mString);
34      mUnicodeString.setTo(false, mChars, charCount);
35    }
36  }
37
38  ~ScopedJavaUnicodeString() {
39    if (mString != NULL) {
40      mEnv->ReleaseStringChars(mString, mChars);
41    }
42  }
43
44  bool valid() const {
45    return (mString != NULL);
46  }
47
48  const icu::UnicodeString& unicodeString() const {
49    return mUnicodeString;
50  }
51
52  icu::UnicodeString& unicodeString() {
53    return mUnicodeString;
54  }
55
56 private:
57  JNIEnv* mEnv;
58  jstring mString;
59  const UChar* mChars;
60  icu::UnicodeString mUnicodeString;
61
62  // Disallow copy and assignment.
63  ScopedJavaUnicodeString(const ScopedJavaUnicodeString&);
64  void operator=(const ScopedJavaUnicodeString&);
65};
66
67#endif  // SCOPED_JAVA_UNICODE_STRING_H_included
68