/**
* Returns <code>true</code> iff the given field is 'subclass-final' and there is at least one
* callable constructor where the field's content can be predicted.
*/
public boolean isGood(HField hf) {
if (hf.isStatic()) return false;
if (badFields.contains(hf)) return false;
// get declared methods of class (should include all constructors)
List l = Arrays.asList(hf.getDeclaringClass().getDeclaredMethods());
// for each callable constructor...
for (Iterator it = l.iterator(); it.hasNext(); ) {
HMethod hm = (HMethod) it.next();
if (!ch.callableMethods().contains(hm)) continue;
if (!isConstructor(hm)) continue;
// okay, hm is a callable constructor.
Map map = classifyMethod(hm);
if (!map.containsKey(hf) || ((Classification) map.get(hf)).isGood())
return true; // this is a good field.
}
return false; // nothing good about this.
}
private Object lookup(Info info, HField hf) {
Object o = ro.get(hf, info);
if (o != ro.NOT_A_VALUE) return o;
if (info instanceof ArrayInfo && hf.getName().equals("length"))
// XXX should wrap more precisely based on hf.getType().
// (arrays may have small length fields in future)
return new Integer(((ArrayInfo) info).length());
assert info instanceof ObjectInfo : "field of array not given a value: " + hf + " / " + info;
return ((ObjectInfo) info).get(hf);
}
/**
* @return the offset of of <code>hf</code> from the initial field. For instance, if <code>hf
* </code> is the 3rd field in its class, <code>getFieldOffset</code> returns 2.
*/
public int getFieldOffset(HField hf) {
return m_hcim.get(hf.getDeclaringClass()).getOffset(hf);
}
/**
* Returns the constant value which field <code>hf</code> is set to whenever the given constructor
* is executed. Requires that <code>isConstant(constructor,hf)</code> be <code>true</code>.
*/
public Object constantValue(HMethod constructor, HField hf) {
assert isConstant(constructor, hf);
Classification c = (Classification) classifyMethod(constructor).get(hf);
return (c == null) ? makeZero(hf.getType()) : c.constant;
}
/** utility function copied from Interpret/Quads/Ref.java */
static final Object defaultValue(HField f) {
if (f.isConstant()) return f.getConstant();
return defaultValue(f.getType());
}