1 /*
2  * Copyright (C) 2008 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 #include "java_lang_String.h"
18 
19 #include "common_throws.h"
20 #include "jni_internal.h"
21 #include "mirror/array.h"
22 #include "mirror/object-inl.h"
23 #include "mirror/string.h"
24 #include "mirror/string-inl.h"
25 #include "scoped_fast_native_object_access.h"
26 #include "scoped_thread_state_change.h"
27 #include "ScopedLocalRef.h"
28 #include "verify_object-inl.h"
29 
30 namespace art {
31 
String_charAt(JNIEnv * env,jobject java_this,jint index)32 static jchar String_charAt(JNIEnv* env, jobject java_this, jint index) {
33   ScopedFastNativeObjectAccess soa(env);
34   return soa.Decode<mirror::String*>(java_this)->CharAt(index);
35 }
36 
String_compareTo(JNIEnv * env,jobject java_this,jobject java_rhs)37 static jint String_compareTo(JNIEnv* env, jobject java_this, jobject java_rhs) {
38   ScopedFastNativeObjectAccess soa(env);
39   if (UNLIKELY(java_rhs == nullptr)) {
40     ThrowNullPointerException("rhs == null");
41     return -1;
42   } else {
43     return soa.Decode<mirror::String*>(java_this)->CompareTo(soa.Decode<mirror::String*>(java_rhs));
44   }
45 }
46 
String_concat(JNIEnv * env,jobject java_this,jobject java_string_arg)47 static jstring String_concat(JNIEnv* env, jobject java_this, jobject java_string_arg) {
48   ScopedFastNativeObjectAccess soa(env);
49   if (UNLIKELY(java_string_arg == nullptr)) {
50     ThrowNullPointerException("string arg == null");
51     return nullptr;
52   }
53   StackHandleScope<2> hs(soa.Self());
54   Handle<mirror::String> string_this(hs.NewHandle(soa.Decode<mirror::String*>(java_this)));
55   Handle<mirror::String> string_arg(hs.NewHandle(soa.Decode<mirror::String*>(java_string_arg)));
56   int32_t length_this = string_this->GetLength();
57   int32_t length_arg = string_arg->GetLength();
58   if (length_arg > 0 && length_this > 0) {
59     mirror::String* result = mirror::String::AllocFromStrings(soa.Self(), string_this, string_arg);
60     return soa.AddLocalReference<jstring>(result);
61   }
62   jobject string_original = (length_this == 0) ? java_string_arg : java_this;
63   return reinterpret_cast<jstring>(string_original);
64 }
65 
String_fastIndexOf(JNIEnv * env,jobject java_this,jint ch,jint start)66 static jint String_fastIndexOf(JNIEnv* env, jobject java_this, jint ch, jint start) {
67   ScopedFastNativeObjectAccess soa(env);
68   // This method does not handle supplementary characters. They're dealt with in managed code.
69   DCHECK_LE(ch, 0xffff);
70   return soa.Decode<mirror::String*>(java_this)->FastIndexOf(ch, start);
71 }
72 
String_fastSubstring(JNIEnv * env,jobject java_this,jint start,jint length)73 static jstring String_fastSubstring(JNIEnv* env, jobject java_this, jint start, jint length) {
74   ScopedFastNativeObjectAccess soa(env);
75   StackHandleScope<1> hs(soa.Self());
76   Handle<mirror::String> string_this(hs.NewHandle(soa.Decode<mirror::String*>(java_this)));
77   gc::AllocatorType allocator_type = Runtime::Current()->GetHeap()->GetCurrentAllocator();
78   mirror::String* result = mirror::String::AllocFromString<true>(soa.Self(), length, string_this,
79                                                                  start, allocator_type);
80   return soa.AddLocalReference<jstring>(result);
81 }
82 
String_getCharsNoCheck(JNIEnv * env,jobject java_this,jint start,jint end,jcharArray buffer,jint index)83 static void String_getCharsNoCheck(JNIEnv* env, jobject java_this, jint start, jint end,
84                                    jcharArray buffer, jint index) {
85   ScopedFastNativeObjectAccess soa(env);
86   StackHandleScope<1> hs(soa.Self());
87   Handle<mirror::CharArray> char_array(hs.NewHandle(soa.Decode<mirror::CharArray*>(buffer)));
88   soa.Decode<mirror::String*>(java_this)->GetChars(start, end, char_array, index);
89 }
90 
String_intern(JNIEnv * env,jobject java_this)91 static jstring String_intern(JNIEnv* env, jobject java_this) {
92   ScopedFastNativeObjectAccess soa(env);
93   mirror::String* s = soa.Decode<mirror::String*>(java_this);
94   mirror::String* result = s->Intern();
95   return soa.AddLocalReference<jstring>(result);
96 }
97 
String_setCharAt(JNIEnv * env,jobject java_this,jint index,jchar c)98 static void String_setCharAt(JNIEnv* env, jobject java_this, jint index, jchar c) {
99   ScopedFastNativeObjectAccess soa(env);
100   soa.Decode<mirror::String*>(java_this)->SetCharAt(index, c);
101 }
102 
String_toCharArray(JNIEnv * env,jobject java_this)103 static jcharArray String_toCharArray(JNIEnv* env, jobject java_this) {
104   ScopedFastNativeObjectAccess soa(env);
105   mirror::String* s = soa.Decode<mirror::String*>(java_this);
106   return soa.AddLocalReference<jcharArray>(s->ToCharArray(soa.Self()));
107 }
108 
109 static JNINativeMethod gMethods[] = {
110   NATIVE_METHOD(String, charAt, "!(I)C"),
111   NATIVE_METHOD(String, compareTo, "!(Ljava/lang/String;)I"),
112   NATIVE_METHOD(String, concat, "!(Ljava/lang/String;)Ljava/lang/String;"),
113   NATIVE_METHOD(String, fastIndexOf, "!(II)I"),
114   NATIVE_METHOD(String, fastSubstring, "!(II)Ljava/lang/String;"),
115   NATIVE_METHOD(String, getCharsNoCheck, "!(II[CI)V"),
116   NATIVE_METHOD(String, intern, "!()Ljava/lang/String;"),
117   NATIVE_METHOD(String, setCharAt, "!(IC)V"),
118   NATIVE_METHOD(String, toCharArray, "!()[C"),
119 };
120 
register_java_lang_String(JNIEnv * env)121 void register_java_lang_String(JNIEnv* env) {
122   REGISTER_NATIVE_METHODS("java/lang/String");
123 }
124 
125 }  // namespace art
126