Java使用注解和反射简化编程的方法示例

import java.lang.annotation.Annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import java.lang.reflect.Method;
import java.util.ArrayList;
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@interface testAnnoation10 {
  public String name() default "methodname";
  public String unit() default "unit";
}
public class ch11_10 {
  public static void main( String[] args ) throws Exception {
    ch11_10 ch9 = new ch11_10();
    Method method[] = ch9.getClass().getMethods();
    for (Method method2 : method) {
      Annotation annotation = method2.getAnnotation(testAnnoation10.class);
      Class<?> ts[] = method2.getParameterTypes();
      if (method2.getName().indexOf("getData") == -1) continue;
      ArrayList<Object> params = new ArrayList<Object>();
      for (Class<?> class1 : ts) {
        if (class1.getSimpleName().equals("int")) {
          params.add(10);
        }
        if (class1.getSimpleName().equals("String")) {
          params.add("100");
        }
      }
      if (annotation != null) {
        testAnnoation10 t9 = (testAnnoation10) annotation;
        System.out.println(t9.name() + " is " + method2.invoke(ch9, params.toArray()) + " " + t9.unit());
      }
    }
  }
  @testAnnoation10(name = "SOC", unit = "%")
  public int getData1( int a ) {
    return a;
  }
  @testAnnoation10(name = "Electricity", unit = "Ah")
  public String getData2( String b ) {
    return b;
  }
  @testAnnoation10(name = "Tempreture", unit = "AF")
  public int getData3( int a, int b ) {
    return a + b;
  }
}