src/xdf/src/main/java/jp/ac/aiit/xdf/utils/Reflections.java

   1 package jp.ac.aiit.xdf.utils;
   2
   3 import java.lang.reflect.Constructor;
   4 import java.lang.reflect.InvocationTargetException;
   5 import java.lang.reflect.Method;
   6
   7 import jp.ac.aiit.xdf.core.exceptions.UnexpectedBehaviorException;
   8
   9 /**
  10  * @author Shunichi Takagi
  11  */
  12 public class Reflections {
  13
  14         public static Object getInstance(String className) {
  15                 try {
  16                         return Reflections.getInstance(Class.forName(className));
  17                 } catch (ClassNotFoundException e) {
  18                         throw new UnexpectedBehaviorException("specified class is not exists : " + className);
  19                 }
  20         }
  21
  22         public static <T> T getInstance(Class<T> clazz) {
  23                 try {
  24                         return clazz.newInstance();
  25                 } catch (InstantiationException e) {
  26                         throw new UnexpectedBehaviorException("class instantiation failed : "+clazz.getCanonicalName(), e);
  27                 } catch (IllegalAccessException e) {
  28                         throw new UnexpectedBehaviorException("access illegal constructor : "+clazz.getCanonicalName()+"()", e);
  29                 }
  30         }
  31
  32         public static Object getInstance(String className, Object ...params) {
  33                 try {
  34                         return Reflections.getInstance(Class.forName(className), params);
  35                 } catch (ClassNotFoundException e) {
  36                         throw new UnexpectedBehaviorException("specified class is not exists : " + className);
  37                 }
  38         }
  39
  40         public static <T> T getInstance(Class<T> clazz, Object ...params) {
  41                 Class<?>[] parameterTypes = new Class[params.length];
  42                 for(int i=0; i<params.length; i++) {
  43                         parameterTypes[i] = params[i].getClass();
  44                 }
  45
  46                 try {
  47                         Constructor<T> constructor = clazz.getConstructor(parameterTypes);
  48                         return constructor.newInstance(params);
  49                 } catch (SecurityException e) {
  50                         throw new UnexpectedBehaviorException("security exception", e);
  51                 } catch (NoSuchMethodException e) {
  52                         throw new UnexpectedBehaviorException("no such method exception", e);
  53                 } catch (InstantiationException e) {
  54                         throw new UnexpectedBehaviorException("class instantiation failed : "+clazz.getCanonicalName(), e);
  55                 } catch (IllegalAccessException e) {
  56                         throw new UnexpectedBehaviorException("access illegal constructor : "+clazz.getCanonicalName(), e);
  57                 } catch (InvocationTargetException e) {
  58                         throw new UnexpectedBehaviorException("invocation target exception", e);
  59                 }
  60         }
  61
  62         public static Object invokeMethod(Object obj, Method method, Object ...args) {
  63                 try {
  64                         Object result = null;
  65
  66                         if( method.isAccessible() ) {
  67                                 result = method.invoke(obj, args);
  68                         } else {
  69                                 method.setAccessible(true);
  70                                 result = method.invoke(obj, args);
  71                                 method.setAccessible(false);
  72                         }
  73
  74                         return result;
  75
  76                 } catch(SecurityException e) {
  77                         throw new UnexpectedBehaviorException(e);
  78                 } catch(IllegalAccessException e) {
  79                         throw new UnexpectedBehaviorException(e);
  80                 } catch(InvocationTargetException e) {
  81                         throw new UnexpectedBehaviorException(e);
  82                 }
  83         }
  84
  85         public static Object invokeMethod(Object obj, String methodName, Object ...args) throws NoSuchMethodException, IllegalArgumentException {
  86                 Class<?> clazz = obj.getClass();
  87
  88                 Class<?>[] types = new Class[args.length];
  89                 for(int i=0; i<args.length; i++) {
  90                         types[i] = args[i].getClass();
  91                 }
  92                 Method method = clazz.getMethod(methodName, types);
  93
  94                 return Reflections.invokeMethod(obj, method, args);
  95
  96         }
  97
  98         public static Object invokeMethod(Object obj, String methodName,  Class<?> types, Object ...args) throws NoSuchMethodException, IllegalArgumentException {
  99                 Class<?> clazz = obj.getClass();
 100
 101                 Method method = clazz.getMethod(methodName, types);
 102
 103                 return Reflections.invokeMethod(obj, method, args);
 104
 105         }
 106 }