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This article introduces the knowledge of "how to load functions in JVM in JAVA". In the operation of actual cases, many people will encounter such a dilemma, so let the editor lead you to learn how to deal with these situations. I hope you can read it carefully and be able to achieve something!

JVM load function

/ *

* Load a jvm from "jvmpath" and initialize the invocation functions.

, /

Jboolean

LoadJavaVM (const char * jvmpath, InvocationFunctions * ifn)

{

HINSTANCE handle

JLI_TraceLauncher ("JVM path is% s\ n", jvmpath)

/ *

* The Microsoft C Runtime Library needs to be loaded first. A copy is

* assumed to be present in the "JRE path" directory. If it is not found

* there (or "JRE path" fails to resolve), skip the explicit load and let

* nature take its course, which is likely to be a failure to execute.

*

, /

LoadMSVCRT ()

/ * Load the Java VM DLL * /

If ((handle = LoadLibrary (jvmpath)) = = 0) {

JLI_ReportErrorMessage (DLL_ERROR4, (char *) jvmpath)

Return JNI_FALSE

}

/ * Now get the function addresses * /

Ifn- > CreateJavaVM =

(void *) GetProcAddress (handle, "JNI_CreateJavaVM")

/ / initialize default parameters

Ifn- > GetDefaultJavaVMInitArgs =

(void *) GetProcAddress (handle, "JNI_GetDefaultJavaVMInitArgs")

If (ifn- > CreateJavaVM = = 0 | | ifn- > GetDefaultJavaVMInitArgs = = 0) {

JLI_ReportErrorMessage (JNI_ERROR1, (char *) jvmpath)

Return JNI_FALSE

}

Return JNI_TRUE

}

/ / default parameter structure

/ *

* This structure is used by the launcher to get the default thread

* stack size from the VM using JNI_GetDefaultJavaVMInitArgs () with a

* version of 1.1. As it is not supported otherwise, it has been removed

* from jni.h

, /

Typedef struct JDK1_1InitArgs {

Jint version

Char * * properties

Jint checkSource

Jint nativeStackSize

Jint javaStackSize

Jint minHeapSize

Jint maxHeapSize

Jint verifyMode

Char * classpath

Jint (JNICALL * vfprintf) (FILE * fp, const char * format, va_list args)

Void (JNICALL * exit) (jint code)

Void (JNICALL * abort) (void)

Jint enableClassGC

Jint enableVerboseGC

Jint disableAsyncGC

Jint verbose

Jboolean debugging

Jint debugPort

} JDK1_1InitArgs

/ / tool function for tracking jvm

Void

JLI_TraceLauncher (const char* fmt,...)

{

Va_list vl

If (_ launcher_debug! = JNI_TRUE) return

Va_start (vl, fmt)

Vprintf (fmt,vl)

Va_end (vl)

Fflush (stdout)

}

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