使用Java实现JS脚本引擎
项目地址
https://github.com/GitHub-Laz...
- 支持解析js脚本生成语法树
- 支持运行完整js脚本
- 支持安全模式运行单行表达式
- 支持设置超时时间
git clone https://github.com/GitHub-Laziji/js-engine.git
cd js-engine
mvn package
cd targetjava -jar ./js-engine-1.0-SNAPSHOT-jar-with-dependencies.jar ./test.js或者安装后直接引入依赖
git clone https://github.com/GitHub-Laziji/js-engine.git
cd js-engine
mvn install
org.laziji.commons
js-engine
1.0-SNAPSHOT
1. 生成语法树 并输出格式化代码 示例代码
class Test{
public static void main(String[] args){
Top.init();
DocNode doc = Top.compile("leta=1+2,b=3,c=\"string\",d=a*(b+c/2),func=function(){};
");
System.out.println(doc);
}
}输出
let a = 1 + 2, b = 3, c = "string", d = a * (b + c / 2), func = function () {}2. 运行完整脚本 【从0到1编写一个JS脚本引擎】以下示例为运行快排算法（运行环境线程隔离）
示例代码
class Test{
/**
* function sort(arr, i, j) {
*if (i >= j) {
*return;
*}
*let p = i, q = j;
*let temp = arr[p];
*while (p < q) {
*while (p < q && arr[q] >= temp) {
*q-=1;
*}
*arr[p] = arr[q];
*while (p < q && arr[p] <= temp) {
*p+=1;
*}
*arr[q] = arr[p];
*}
*arr[q] = temp;
*sort(arr, i, q - 1);
*sort(arr, q + 1, j);
* }
*
* let arr = [234, 57, 12, 123, 346, 1234, 2];
*
* sort(arr, 0, arr.length - 1);
*/
public static void main(String[] args){
Top.init();
Top.eval("function sort(arr, i, j) {\n" +
"if (i >= j) {\n" +
"return;
\n" +
"}\n" +
"let p = i, q = j;
\n" +
"let temp = arr[p];
\n" +
"while (p < q) {\n" +
"while (p < q && arr[q] >= temp) {\n" +
"q-=1;
\n" +
"}\n" +
"arr[p] = arr[q];
\n" +
"while (p < q && arr[p] <= temp) {\n" +
"p+=1;
\n" +
"}\n" +
"arr[q] = arr[p];
\n" +
"}\n" +
"arr[q] = temp;
\n" +
"sort(arr, i, q - 1);
\n" +
"sort(arr, q + 1, j);
\n" +
"}\n" +
"\n" +
"let arr = [234, 57, 12, 123, 346, 1234, 2];
\n" +
"\n" +
"sort(arr, 0, arr.length - 1);
");
Top.loop();
System.out.println(Top.getThreadLocalTop().getMainContexts().getContexts().peek().toSimpleString());
}
}输出
arr: [2, 12, 57, 123, 234, 346, 1234]
sort: [object Object]3. 运行单行表达式 该模式下只支持单行表达式 并且无法使用for、while、function、lambda、import关键字
示例代码
class Test{
public static void main(String[] args){
Top.init();
System.out.println(Top.exprEval("'hello '+(1*2*3*4)"));
}
}输出
hello 244. 设置超时时间 通过
Top.getThreadLocalTop().setOvertime(100L);
设置超时时间，单位毫秒示例代码
class Test{
public static void main(String[] args){
Top.init();
Top.getThreadLocalTop().setOvertime(100L);
Top.addInternalModules("sys", new SystemModuleValue());
Top.eval("import { print } from \"sys\";
\n" +
"\n" +
"let i=1;
\n" +
"while(true){\n" +
"print(i++);
\n" +
"}");
Top.loop();
}
}输出
1
2
3
...org.laziji.commons.js.exception.RunException: Run timeout.
...
