增加 string 类型的接口

Author: durongze

CppCallJni.cpp

@@ -1,6 +1,8 @@
 #include "com_durongze_jni_CallC.h"
 #include <Windows.h>
 
+#include <stdio.h>
+
 #define JAVA_HOME "D:\\Program Files\\Java\\jre1.8.0_60"
 #define JVM_DLL JAVA_HOME "\\bin\\server\\" "jvm.dll"
 
@@ -50,7 +52,12 @@ extern "C" {
 			penv->ReleaseStringUTFChars(ns, 0);
 		}
 
-		jobjectArray res = (jobjectArray)Java_com_durongze_jni_CallC_CInterface(penv, NULL, names, ages, heights, num);
+		jobjectArray res = Java_com_durongze_jni_CallC_CInterface(penv, NULL, names, ages, heights, num);
+		jstring func = penv->NewStringUTF("main");
+		jstring retStr = Java_com_durongze_jni_CallC_CInterfaceString(penv, NULL, func);
+		jboolean b = false;
+		printf("retStr:%s\n", penv->GetStringUTFChars(retStr, &b));
+		penv->ReleaseStringUTFChars(retStr, 0);
 
 		pvm->DestroyJavaVM();
 	}

callc/CMakeLists.txt

@@ -3,9 +3,12 @@ cmake_minimum_required(VERSION 3.4.1)
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DDYZ_DBG")
 set(JAVA_HOME "$ENV{JAVA_HOME}")
 file(GLOB C_LIBRARY_SRC *.cpp *.h)
+#list(REMOVE_ITEM C_LIBRARY_SRC main.cpp)
 
 MESSAGE(STATUS "JAVA_HOME DIR: ${JAVA_HOME} ENV_JAVA_HOME DIR: $ENV{HOME}")
 
 include_directories(${CMAKE_CURRENT_SOURCE_DIR}/ ${JAVA_HOME}/include/ ${JAVA_HOME}/include/win32)
 add_library(CLibrary SHARED ${C_LIBRARY_SRC})
 
+file(GLOB CPP_CALL_JNI_SRC ../*.cpp )
+add_executable(CppCallJni ${C_LIBRARY_SRC} ${CPP_CALL_JNI_SRC})

callc/CallC.java

@@ -3,6 +3,7 @@
 public class CallC{
     public native String[] CInterface(String[] name, int[] age, float[] height, int num);
     public native int CInterfaceTest();
+    public native String CInterfaceString(String func);
     static {
         System.loadLibrary("CLibrary");
     }
@@ -27,5 +28,7 @@ public static void main(String[] args){
         }
         int ret = new CallC().CInterfaceTest();
         System.out.println("ret :" + ret);
+        String retStr = new CallC().CInterfaceString(name[0]);
+        System.out.println("retStr :" + retStr);
     }
 };

callc/com_durongze_jni_CallC.cpp

@@ -113,6 +113,15 @@ JNIEXPORT jint JNICALL Java_com_durongze_jni_CallC_CInterfaceTest
       #endif
   }
 
+JNIEXPORT jstring JNICALL Java_com_durongze_jni_CallC_CInterfaceString
+(JNIEnv *env, jobject, jstring name)
+{
+	jboolean b = false;
+	printf("retStr:%s\n", env->GetStringUTFChars(name, &b));
+	env->ReleaseStringUTFChars(name, 0);
+	return env->NewStringUTF(__FUNCTION__);
+}
+
 #ifdef __cplusplus
 #if __cplusplus
 }