+// 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 {
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();
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) {
if (o==null) return "";
if (!(o instanceof Object[])) return o.toString();
}
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() &&
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 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); }
- }
- 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); }
- }
- 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); }
- }
-
}