Use of Index, Offset and Address of an Item

These fields have different meanings according to what a given item represents. Note: Statements in brackets denote a type, e.g. [Class] means an item of type org.deepjava.classItems.Class.

Classes [Class]

index: Used to number interfaces, which contain methods called by invokeinterface.
offset: Not used, always -1.
address: Contains the absolute address of the type descriptor (field size).

Arrays [Array]

index: Not used, always -1.
offset: Offset in bytes of the type descriptor in the memory segment.
address: Contains the absolute address of the array type descriptor.

Methoden [Method]

index: If instance method → index into method table (starting with 0), if class method → always -1. index is set by the Class File Reader.
offset: Offset in bytes of the method starting from the start address of the code of the class of this method.
address: Contains the absolute address of the method.

Fields [DataItem]

IMPORTANT Constant References

Important: With constant and static references the const flag dpfConst will not be set. Such fields must be handled like regular non constant fields because the class constructor will access such a field exactly once. Example:

static final Object o = new Object();

Class fields [DataItem]:
1. Constant fields [NamedConst]:
  - index: Not used, always -1.
  - offset: not used, always -1.
  - address: not used, always -1.
2. Non-constant fields [DataItem]:
  - index: not used, always -1.
  - offset: Offset in bytes (starting with 0 for the first field).
  - address: Contains the absolute address of the field.
Instanz-Felder [DataItem]:
- index: Not used, always -1.
- offset: Offset in bytes starting with 0 (fields of superclasses are accounted for).
- address: Not used, always -1.

Constants [Constant]

Numbers [StdConstant]:
- index: If of type float or double → index in the const pool. Else always -1.
- offset: If of type float or double → offset in bytes in the const pool. Else always -1.
- address: If of type float or double → absolute address. Else always -1.
Strings [StringLiteral]:
- index: Index in the string pool.
- offset: Offset in bytes in the string pool.
- address: Absolute address.