Class ReflectionUtil

java.lang.Object
jp.ecuacion.lib.core.util.ReflectionUtil
Direct Known Subclasses:
ConstraintViolationBean
public class ReflectionUtil extends Object
Provides utility methods for java.lang.reflect and other checks.

  • Constructor Details

    • ReflectionUtil

      public ReflectionUtil()

  • Method Details

    • classExists

      public static boolean classExists(String className)
      Returns true when designated class exists.
      Parameters:
      className - className with package (like "java.lang.Object")
      Returns:
      boolean

    • newInstance

      public static Object newInstance(String className)
      Returns new instance constructed with an constructor with no arguments.
      Parameters:
      className - className with package (like "java.lang.Object")
      Returns:
      new instance

    • searchAnnotationPlacedAtClass

      public static <A extends Annotation> Optional<A> searchAnnotationPlacedAtClass(Class<?> classOfTargetInstance, Class<A> annotation)
      Searches for a class annotation in the argument class and its superClasses.

      The search starts at the argument instance, and if it doesn't have the annotation, It searches the superClass of the instance next.
      And if it continues to search the annotation and it reaches to Object.class, it stops to search and returns empty Optional.

      Search ends when it founds the first annotation. Even if there is another anntation of same class, it ignores and it returns first-found annotation.

    • getValue

      protected static Object getValue(Object object, String propertyPath)
      Obtains a field value with any scopes and searches fields in super classes.

      Since Class#getDeclaredField is used in the method, making its scope public causes a spotbugs error.
      That's why its scope is protected and when you use it you need to extend this class.

      Public method jp.ecuacion.lib.core.util.internal.PrivateFieldReadUtil.getFieldValue(String, Object, String) uses reflection to modify a field it gets in its parameter which could increase the accessibility of any class. REFLF_REFLECTION_MAY_INCREASE_ACCESSIBILITY_OF_FIELD

    • getField

      @Nonnull public static Field getField(Class<?> object, String fieldName)
      Obtains a field with any scopes and also searches fields in super classes.
      Parameters:
      object - classOfTargetInstance
      fieldName - fieldName
      Returns:
      Pair<Field, Object> left-hand side is the obtained field, right-hand side is its instance. When you set "dept.name" to fieldName, instance would be "dept".