目录

Obtaining the JSVM-API Version Using JSVM-API

Introduction

This topic walks you through how to use JSVM-API to obtain the JSVM-API version.

Available APIs

API Description
OH_JSVM_GetVersion Obtains the latest JSVM API version supported by the JSVM runtime.
OH_JSVM_GetVMInfo Obtains the VM information.

Example

If you are just starting out with JSVM-API, see JSVM-API Development Process. The following demonstrates only the C++ code involved in using version-related APIs.

[h2]OH_JSVM_GetVersion && OH_JSVM_GetVMInfo

Use OH_JSVM_GetVersion && OH_JSVM_GetVMInfo to obtain the latest JSVM API version supported by the current environment and the VM information.

CPP code:

// Define OH_JSVM_GetVersion.
static JSVM_Value GetVersion(JSVM_Env env, JSVM_CallbackInfo info)
{
    uint32_t jsVersion = 0;
    // Obtain the latest JSVM API version supported by the current JSVM runtime.
    JSVM_CALL(OH_JSVM_GetVersion(env, &jsVersion));
    int value = static_cast<int>(jsVersion);
    OH_LOG_INFO(LOG_APP, "JSVM GetVersion success:%{public}d", value);
    return nullptr;
}

// Define OH_JSVM_GetVMInfo.
// Print the JSVM information.
void PrintVmInfo(JSVM_VMInfo vmInfo)
{
    OH_LOG_INFO(LOG_APP, "JSVM API apiVersion: %{public}d", vmInfo.apiVersion);
    OH_LOG_INFO(LOG_APP, "JSVM API engine: %{public}s", vmInfo.engine);
    OH_LOG_INFO(LOG_APP, "JSVM API version: %{public}s", vmInfo.version);
    OH_LOG_INFO(LOG_APP, "JSVM API cachedDataVersionTag: 0x%{public}x", vmInfo.cachedDataVersionTag);
}

static JSVM_Value GetVMInfo(JSVM_Env env, JSVM_CallbackInfo info)
{
    // Obtain the VM information.
    JSVM_VMInfo result;
    JSVM_CALL(OH_JSVM_GetVMInfo(&result));
    // Output the VM information.
    PrintVmInfo(result);
    return nullptr;
}

// Register callbacks for GetVersion and GetVMInfo.
static JSVM_CallbackStruct param[] = {
    {.data = nullptr, .callback = GetVersion},
    {.data = nullptr, .callback = GetVMInfo},
};
static JSVM_CallbackStruct *method = param;
// Aliases for GetVersion and GetVMInfo methods, for JS to call.
static JSVM_PropertyDescriptor descriptor[] = {
    {"getVersion", nullptr, method, nullptr, nullptr, nullptr, JSVM_DEFAULT},
    {"getVMInfo", nullptr, method + 1, nullptr, nullptr, nullptr, JSVM_DEFAULT},
};

// Sample test JS.
static const char *STR_TASK = R"JS(getVersion();getVMInfo();)JS";

Expected result:

JSVM GetVersion success:9
JSVM API apiVersion: 1
JSVM API engine: v8
JSVM API version: 13.2.152.41
JSVM API cachedDataVersionTag: 0x81ff9402