A field list component is a primative part of a virtual machine. It can
exist outside a virtual machine for extreme testing. In other words, it can
be completely tested /before/ it is integrated into your virtual machine.
A field list is a component of each object. Just as it has a method list,
an object has a field list. A field list can be used to store static fields
for a class and instance fields for an object. And it looks as if the field
list component could be reusable by the stack frame for local variables, too.
A field list allocates room for fields when it is open'd. To initialize a
field list, repeatedly call its addField() method for each field. The
addField() method has a prototype like this:
void FieldList::addField( const char *fieldSpec, const char *descriptor );
where fieldSpec is a full field name (java/lang/System/out) and descriptor
is the field type (Ljava/io/InputStream;).
When open'd, the FieldList also creates a cross-reference index, so that
fields can be addressed by their ID rather than by their name. FieldList
provides a method to get a field ID:
short FieldList::getFieldID( const char *fieldSpec );
To get/set a four-octet field, use
getIntField( short id );
getIntField( const char *fieldSpec );
setIntField( short id, jint v );
setIntField( const char *fieldSpec, jint v );
To get/set an eight-octet field, use
getLongField( short id );
getLongField( const char *fieldSpec );
setLongField( short id, jlong v );
setLongField( const char *fieldSpec, jlong v );
Different field list components are possible. Some might organize fields
into a linked list, an array, or allocate a single block of memory for all
fields in the list.
_______________________________________________
Kernel maillist - [EMAIL PROTECTED]
http://jos.org/mailman/listinfo/kernel
