base/android/jni_array.h: Add JavaArrayOfByteArraysToStringVector()

This will be used by the SSL client certificate support code to
return the certificate chain as a vector of DER-encoded X.509
certificates.

BUG=none


Review URL: https://chromiumcodereview.appspot.com/11418287

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@171224 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 62 insertions, 0 deletions

diff --git a/base/android/jni_array.cc b/base/android/jni_array.cc
index 53027c7..9b12531 100644
--- a/base/android/jni_array.cc
+++ b/base/android/jni_array.cc
@@ -127,5 +127,23 @@ void JavaIntArrayToIntVector(JNIEnv* env,
   env->ReleaseIntArrayElements(array, ints, JNI_ABORT);
 }
 
+void JavaArrayOfByteArrayToStringVector(
+    JNIEnv* env,
+    jobjectArray array,
+    std::vector<std::string>* out) {
+  DCHECK(out);
+  out->clear();
+  jsize len = env->GetArrayLength(array);
+  for (jsize i = 0; i < len; ++i) {
+    jbyteArray bytes_array = static_cast<jbyteArray>(
+        env->GetObjectArrayElement(array, i));
+    jsize bytes_len = env->GetArrayLength(bytes_array);
+    jbyte* bytes = env->GetByteArrayElements(bytes_array, NULL);
+    out->push_back(
+        std::string(reinterpret_cast<const char*>(bytes), bytes_len));
+    env->ReleaseByteArrayElements(bytes_array, bytes, JNI_ABORT);
+  }
+}
+
 }  // namespace android
 }  // namespace base
diff --git a/base/android/jni_array.h b/base/android/jni_array.h
index 86433a3..fbc131e 100644
--- a/base/android/jni_array.h
+++ b/base/android/jni_array.h
@@ -59,6 +59,14 @@ BASE_EXPORT void JavaIntArrayToIntVector(
     jintArray int_array,
     std::vector<int>* out);
 
+// Assuming |array| is an byte[][] (array of byte arrays), replaces the
+// content of |out| with the corresponding vector of strings. No UTF-8
+// conversion is performed.
+void JavaArrayOfByteArrayToStringVector(
+    JNIEnv* env,
+    jobjectArray array,
+    std::vector<std::string>* out);
+
 }  // namespace android
 }  // namespace base
 
diff --git a/base/android/jni_array_unittest.cc b/base/android/jni_array_unittest.cc
index 7529335..a4e3025 100644
--- a/base/android/jni_array_unittest.cc
+++ b/base/android/jni_array_unittest.cc
@@ -27,5 +27,41 @@ TEST(JniArray, BasicConversions) {
   EXPECT_EQ(8U, vec.size());
 }
 
+TEST(JniArray, JavaArrayOfByteArrayToStringVector) {
+  const int kMaxItems = 50;
+  JNIEnv* env = AttachCurrentThread();
+
+  // Create a byte[][] object.
+  ScopedJavaLocalRef<jclass> byte_array_clazz(env, env->FindClass("[B"));
+  ASSERT_TRUE(byte_array_clazz.obj());
+
+  ScopedJavaLocalRef<jobjectArray> array(
+      env, env->NewObjectArray(kMaxItems, byte_array_clazz.obj(), NULL));
+  ASSERT_TRUE(array.obj());
+
+  // Create kMaxItems byte buffers.
+  char text[16];
+  for (int i = 0; i < kMaxItems; ++i) {
+    snprintf(text, sizeof text, "%d", i);
+    ScopedJavaLocalRef<jbyteArray> byte_array = ToJavaByteArray(
+        env, reinterpret_cast<uint8*>(text),
+        static_cast<size_t>(strlen(text)));
+    ASSERT_TRUE(byte_array.obj());
+
+    env->SetObjectArrayElement(array.obj(), i, byte_array.obj());
+    ASSERT_FALSE(HasException(env));
+  }
+
+  // Convert to std::vector<std::string>, check the content.
+  std::vector<std::string> vec;
+  JavaArrayOfByteArrayToStringVector(env, array.obj(), &vec);
+
+  EXPECT_EQ(static_cast<size_t>(kMaxItems), vec.size());
+  for (int i = 0; i < kMaxItems; ++i) {
+    snprintf(text, sizeof text, "%d", i);
+    EXPECT_STREQ(text, vec[i].c_str());
+  }
+}
+
 }  // namespace android
 }  // namespace base