javascript - 我想加快 Nashorn 的评估速度

Question

我被允许运行 zxcvbn.js (Javascript library)到纳肖恩。但有一个问题。

eval(预编译)非常慢。大约需要3分钟。我想 Action 更快。

public class StrengthChecker {

  private static final String ZXCVBN_PATH = "/META-INF/resources/webjars/zxcvbn/1.0/zxcvbn.js";

  private final ScriptEngine engine;

  public StrengthChecker() {
    ScriptEngineManager manager = new ScriptEngineManager();
    engine = manager.getEngineByName("nashorn");

    Bindings engineScope = engine.getBindings(ScriptContext.ENGINE_SCOPE);
    engineScope.put("window", engineScope);

    try {

      // -------------------------------------------
      // Here is very slow definition of zxcvbn.js.
      // -------------------------------------------
      engine.eval(getResourceContents(ZXCVBN_PATH));

    } catch (ScriptException e) {
      throw new RuntimeException(e);
    }
  }

  public Strength check(String pw) {
    try {
      Map<String, Object> result;
      result = (Map<String, Object>) engine.eval("zxcvbn('" + pw + "');");

      return new Strength(
        ((Double) result.get("entropy")).intValue(),
        (int) result.get("score"),
        ((Double) result.get("crack_time")).intValue()
      );
    } catch (ScriptException e) {
      throw new RuntimeException(e);
    }
  }

}

请告诉我们一些解决方案。

Answer 1

这是一个已知的性能错误，已修复，请参阅 https://bugs.openjdk.java.net/browse/JDK-8137333 。它应该与 Java 8u72 一起发布，预计于 2016 年 1 月发布。Java 9 的预发布版本可在 https://jdk9.java.net/download/ 获取。还包含修复程序(自 JDK9 构建 b85 起)。