java - 在 Grails 中调用 Java 代码时出错

Question

我在从 Grails 应用程序调用 java 类时遇到问题。

Controller 类:

class MyController{

    def index() { 
         somepkg.MyJavaClass.method()
    }
}

Java 类:

package somepkg;

public class MyJavaClass{

    public void method() {
           // ... some logic here
    }
}

错误:

No signature of method: static somepkg.MyJavaClass.method() is applicable for argument types: () values: [] Possible solutions: wait(), any(), find(), wait(long), each(groovy.lang.Closure), find(groovy.lang.Closure)

Answer 1

如果您想在不创建实例的情况下调用类的方法，则必须将该方法标记为静态:

public static void afada() throws FileNotFoundException, UnsupportedEncodingException{
  PrintWriter writer = new PrintWriter("ediOrder.txt", "UTF-8");
  writer.println("a");
  writer.close();
}

或者您必须先创建一个实例:

new examplepkg.testing().afada()