In Android development, using JNI (Java Native Interface) allows us to call local code written in C/C++ in Java code. However, during JNI development, debugging native code may be difficult because Android Studio's debugging tools cannot be used directly. In this case, we can use the Log output to help us debug the JNI code. This article will introduce how to use Log to output debugging information in Android JNI and provide corresponding source code examples.
First, we need to use Android's logging library in the JNI code to output debugging information. Android's log library provides a series of output levels, including VERBOSE, DEBUG, INFO, WARN and ERROR. We can choose the appropriate level to output corresponding debugging information as needed. In JNI code, we can use the following methods to output log information:
#include <android/log.h>
#define LOG_TAG "JNI_DEBUG"
#define LOGV(...) __android_log_print(ANDROID_LOG_VERBOSE, LOG_TAG, __VA_ARGS__)
#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, LOG_TAG, __VA_ARGS__)
#define LOGI(...) __android_log_print(ANDROID_LOG_INFO, LOG_TAG, __VA_ARGS__)
#define LOGW(...) __android_log_print(ANDROID_LOG_WARN, LOG_TAG, __VA_ARGS__)
#define LOGE(...) __android_log_print(ANDROID_LOG_ERROR, LOG_TAG, __VA_ARGS__)
In the code above, we