X-Git-Url: http://git.megacz.com/?p=sbp.git;a=blobdiff_plain;f=src%2Fedu%2Fberkeley%2Fsbp%2Futil%2FReflection.java;h=1bd7ffc4846a7c7ba651987174467e7d4aa40b4d;hp=3a129d48db8b89c21515aba9102a63b0f2a93a87;hb=3ee451bce342d4bb61ad6235ba57bdf817bfdd1a;hpb=0f0ed458838eb080e12ad9a52a46a4060d40df43

diff --git a/src/edu/berkeley/sbp/util/Reflection.java b/src/edu/berkeley/sbp/util/Reflection.java
index 3a129d4..1bd7ffc 100644
--- a/src/edu/berkeley/sbp/util/Reflection.java
+++ b/src/edu/berkeley/sbp/util/Reflection.java
@@ -1,8 +1,11 @@
+// Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
+
 package edu.berkeley.sbp.util;
 import java.io.*;
 import java.lang.reflect.*;
 import java.lang.annotation.*;
 
+// FIXME: decent error reporting
 /** Random reflection-related utilities */
 public final class Reflection {
     
@@ -54,7 +57,7 @@ public final class Reflection {
 
     public static String show(Object o) {
         if (o==null) return "null";
-        if (o instanceof Show) return ((Show)o).toString();
+        if (o instanceof Show) return show((Show)o);
         if (! (o instanceof Object[])) return o.toString() + " : " + o.getClass().getName();
         Object[] arr = (Object[])o;
         StringBuffer ret = new StringBuffer();
@@ -210,62 +213,67 @@ public final class Reflection {
         return null;
     }
     public static Object impose(Class _class, Object[] fields) {
-        try {
-            Object ret = _class.newInstance();
-            Field[] f = _class.getFields();
-            int j = 0;
-            for(int i=0; i<f.length; i++) {
-                Object tgt = Reflection.lub(fields[i]);
-                if (f[i].getType() == String.class) tgt = stringify(tgt);
-                // FUGLY
-                tgt = coerce(tgt, f[i].getType());
-                System.err.println("setting a " + f[i].getType().getName() + " to " + Reflection.show(tgt));
+        Object ret = null;
+        try { ret = _class.newInstance(); }
+        catch (Exception e) { rethrow(e, "while trying to instantiate a " + _class.getName()); }
+        Field[] f = _class.getFields();
+        int j = 0;
+        for(int i=0; i<f.length; i++) {
+            Object tgt = Reflection.lub(fields[i]);
+            if (f[i].getType() == String.class) tgt = stringify(tgt);
+            // FUGLY
+            tgt = coerce(tgt, f[i].getType());
+            try {
                 f[i].set(ret, tgt);
+            } catch (Exception e) {
+                rethrow(e, "while setting \n    " +
+                        f[i] +
+                        "\n     to " + show(tgt));
             }
-            return ret;
-        } catch (Exception e) {
-            e.printStackTrace();
-            throw new RuntimeException(e);
         }
+        return ret;
+    }
+
+    public static Object rethrow(Exception e, String message) {
+        e.printStackTrace();
+        StackTraceElement[] st = e.getStackTrace();
+        RuntimeException re = new RuntimeException(e.getMessage() + "\n  " + message);
+        re.setStackTrace(st);
+        throw re;
     }
 
     public static Object impose(Method _method, Object[] fields) {
+        Object[] args = mkArgs(_method.getParameterTypes(), fields);
         try {
-            Class[] argTypes = _method.getParameterTypes();
-            Object[] args = new Object[argTypes.length];
-            int j = 0;
-            for(int i=0; i<args.length; i++) {
-                Object tgt = Reflection.lub(fields[i]);
-                if (argTypes[i] == String.class) tgt = Reflection.stringify(tgt);
-                // FUGLY
-                tgt = Reflection.coerce(tgt, argTypes[i]);
-                System.err.println("setting a " + argTypes[i].getName() + " to " + Reflection.show(tgt));
-                args[i] = tgt;
-            }
-            System.err.println("invoking " + _method + " with " + Reflection.show(args));
             return _method.invoke(null, args);
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            return rethrow(e, "while trying to invoke \n    " +
+                           _method +
+                           "\n    with arguments " + show(args));
         }
     }
-
     public static Object impose(Constructor _ctor, Object[] fields) {
+        Object[] args = mkArgs(_ctor.getParameterTypes(), fields);
         try {
-            Class[] argTypes = _ctor.getParameterTypes();
-            Object[] args = new Object[argTypes.length];
-            int j = 0;
-            for(int i=0; i<args.length; i++) {
-                Object tgt = Reflection.lub(fields[i]);
-                if (argTypes[i] == String.class) tgt = Reflection.stringify(tgt);
-                // FUGLY
-                tgt = Reflection.coerce(tgt, argTypes[i]);
-                System.err.println("setting a " + argTypes[i].getName() + " to " + Reflection.show(tgt));
-                args[i] = tgt;
-            }
             return _ctor.newInstance(args);
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            return rethrow(e, "while trying to invoke \n    " +
+                           _ctor +
+                           "\n    with arguments " + show(args));
+        }
+    }
+
+    private static Object[] mkArgs(Class[] argTypes, Object[] fields) {
+        int j = 0;
+        Object[] args = new Object[argTypes.length];
+        for(int i=0; i<args.length; i++) {
+            Object tgt = Reflection.lub(fields[i]);
+            if (argTypes[i] == String.class) tgt = Reflection.stringify(tgt);
+            // FUGLY
+            tgt = Reflection.coerce(tgt, argTypes[i]);
+            args[i] = tgt;
         }
+        return args;
     }
 
     public static String stringify(Object o) {
@@ -279,11 +287,22 @@ public final class Reflection {
     }
 
     public static Object coerce(Object o, Class c) {
+        try {
+            return coerce0(o, c);
+        } catch (Exception e) {
+            return (Object[])rethrow(e, "while trying to coerce " + show(o) + " to a " + c.getName());
+        }
+    }
+    public static Object coerce0(Object o, Class c) {
         if (o==null) return null;
         if (c.isInstance(o)) return o;
         if (c == char.class) {
             return o.toString().charAt(0);
         }
+        if (c==int.class || c==Integer.class) {
+            String s = (String)coerce(o, String.class);
+            return new Integer(Integer.parseInt(s));
+        }
 
         if (o.getClass().isArray() &&
             o.getClass().getComponentType().isArray() &&
@@ -311,77 +330,14 @@ public final class Reflection {
             for(int i=0; i<((Object[])o).length; i++) {
                 Object ob = (((Object[])o)[i]);
                 if (ob != null) {
-                    System.err.println("no hit with " + c.getComponentType().getName() + " on " + Reflection.show(((Object[])o)[i]));
                     ok = false;
                 }
             }
             if (ok) {
-                System.err.println("hit with " + c.getComponentType().getName());
                 return Array.newInstance(c.getComponentType(), ((Object[])o).length);
             }
         }
         return o;
     }
 
-    public static abstract class Bindable {
-        public abstract String getSimpleName();
-        public abstract String toString();
-        public abstract <A extends Annotation> A getAnnotation(Class<A> c);
-        public abstract Object impose(Object[] fields);
-        public boolean isAnnotationPresent(Class<? extends Annotation> c) { return getAnnotation(c) != null; }
-
-        public abstract Annotation[][] getArgAnnotations();
-        public abstract String[]       getArgNames();
-
-        public static Bindable create(Object o) {
-            if (o instanceof Class) return new BindableClass((Class)o);
-            if (o instanceof Method) return new BindableMethod((Method)o);
-            if (o instanceof Constructor) return new BindableConstructor((Constructor)o);
-            return null;
-        }
-    }
-
-    private static class BindableMethod extends Bindable {
-        private final Method _method;
-        public String toString() { return "BindableMethod["+_method+"]"; }
-        public BindableMethod(Method _method) { this._method = _method; }
-        public String getSimpleName() { return _method.getName(); }
-        public <A extends Annotation> A getAnnotation(Class<A> c) { return _method.getAnnotation(c); }
-        public Object impose(Object[] fields) { return Reflection.impose(_method, fields); }
-        public Annotation[][] getArgAnnotations() { return _method.getParameterAnnotations(); }
-        public String[]       getArgNames() { return new String[_method.getParameterTypes().length]; }
-    }
-    private static class BindableConstructor extends Bindable {
-        private final Constructor _constructor;
-        public String toString() { return "BindableConstructor["+_constructor+"]"; }
-        public BindableConstructor(Constructor _constructor) { this._constructor = _constructor; }
-        public String getSimpleName() { return _constructor.getName(); }
-        public <A extends Annotation> A getAnnotation(Class<A> c) { return _constructor.getAnnotation(c); }
-        public Object impose(Object[] fields) { return Reflection.impose(_constructor, fields); }
-        public Annotation[][] getArgAnnotations() { return _constructor.getParameterAnnotations(); }
-        public String[]       getArgNames() { return new String[_constructor.getParameterTypes().length]; }
-    }
-    private static class BindableClass extends Bindable {
-        private final Class _class;
-        public String toString() { return "BindableClass["+_class+"]"; }
-        public BindableClass(Class _class) { this._class = _class; }
-        public String getSimpleName() { return _class.getSimpleName(); }
-        public <A extends Annotation> A getAnnotation(Class<A> c) { return (A)_class.getAnnotation(c); }
-        public Object impose(Object[] fields) { return Reflection.impose(_class, fields); }
-        public Annotation[][] getArgAnnotations() {
-            Field[] fields = _class.getFields();
-            Annotation[][] ret = new Annotation[fields.length][];
-            for(int i=0; i<fields.length; i++)
-                ret[i] = fields[i].getAnnotations();
-            return ret;
-        }
-        public String[]       getArgNames() {
-            Field[] fields = _class.getFields();
-            String[] ret = new String[fields.length];
-            for(int i=0; i<fields.length; i++)
-                ret[i] = fields[i].getName();
-            return ret;
-        }
-    }
-
 }