我得到的C++结构在头文件,JNI findClass的返回NULL
struct StatusLine
{
static jclass Class; // Lorg/apache/http/StatusLine;
static jmethodID GetStatusCode; //()I
};
struct ByteArrayOutputStream
{
static jclass Class; // Ljava/io/ByteArrayOutputStream;
static jmethodID Constructor; //()V
static jmethodID Close; //()V
static jmethodID ToByteArray; //()[B
};
struct HttpEntity
{
static jclass Class; // Lorg/apache/http/HttpEntity;
static jmethodID WriteTo; // (Ljava/io/OutputStream;)V
static jmethodID GetContent; //()Ljava/io/InputStream;
};
和CPP文件是
#define JAVA_STATUS_LINE_CLASS "org/apache/http/StatusLine"
#define JAVA_HTTP_ENTITY_CLASS "org/apache/http/HttpEntity"
#define JAVA_BYTE_ARRAY_OUTPUT_STREAM_CLASS "java/io/ByteArrayOutputStream"
jclass StatusLine::Class = 0;
jmethodID StatusLine::GetStatusCode = 0;
jclass ByteArrayOutputStream::Class = 0;
jmethodID ByteArrayOutputStream::Constructor = 0;
jmethodID ByteArrayOutputStream::Close = 0;
jmethodID ByteArrayOutputStream::ToByteArray = 0;
jclass HttpEntity::Class = 0;
jmethodID HttpEntity::WriteTo = 0;
jmethodID HttpEntity::GetContent = 0;
void initializeJniPointers()
{
StatusLine::Class = GetJniEnv()->FindClass(JAVA_STATUS_LINE_CLASS);
StatusLine::GetStatusCode = GetJniEnv()->GetMethodID(StatusLine::Class, "getStatusCode", "()I");
ByteArrayOutputStream::Class = GetJniEnv()->FindClass(JAVA_BYTE_ARRAY_OUTPUT_STREAM_CLASS);
ByteArrayOutputStream::Constructor = GetJniEnv()->GetMethodID(ByteArrayOutputStream::Class, "<init>", "()V");
ByteArrayOutputStream::Close = GetJniEnv()->GetMethodID(ByteArrayOutputStream::Class, "close", "()V");
ByteArrayOutputStream::ToByteArray = GetJniEnv()->GetMethodID(ByteArrayOutputStream::Class, "toByteArray", "()[B");
HttpEntity::Class = GetJniEnv()->FindClass(JAVA_HTTP_ENTITY_CLASS);
HttpEntity::WriteTo = GetJniEnv()->GetMethodID(HttpEntity::Class, "writeTo", "(Ljava/io/OutputStream;)V");
HttpEntity::GetContent = GetJniEnv()->GetMethodID(HttpEntity::Class, "getContent", "()Ljava/io/InputStream;");
}
功能initializeJniPointers()压碎上线状态行:: GetStatusCode = GetJniEnv() - >的GetMethodID();因为StatusLine :: Class是NULL。 但是!我注意到: 如果我写这个项目 状态行升一些Java文件=新StatuLine(){ ... }
功能上ByteArrayOutputStream击碎::构造,因为ByteArrayOutputStream ::类为null ,如果我在java中创建一个ByteArrayOutputStream对象,函数将进一步到下一个对象,等等......我注意到:如果我只声明ByteArrayOutputStream的变量,findClass将返回NULL。
有人能解释我该怎么做吗?顺便说一下,我使用Android 2.3.5设备三星GT-S5363,我尝试了其他android(老人)和设备的顶点,它工作正常。
我想是的,因为我加载类manualy后,指针返回正常。但是,只有Android 2.x版本才会出现此问题。在Android 4.x版本上,该错误没有发生。 – theroom101 2015-01-15 13:09:50
对我来说,这个问题只发生在Android> 5.0 – DisableR 2015-01-15 13:16:05
虽然没有在<4.0.4上测试过这个解决方案。 – DisableR 2015-01-15 17:33:18