org.objectweb.asm.attrs
Class AnnotationDefaultAttribute
java.lang.Object
org.objectweb.asm.Attribute
org.objectweb.asm.attrs.AnnotationDefaultAttribute
- Direct Known Subclasses:
- ASMAnnotationDefaultAttribute
public class AnnotationDefaultAttribute
- extends Attribute
The AnnotationDefault attribute is a variable length attribute in the
attributes table of certain method_info structures, namely those representing
elements of annotation types. The AnnotationDefault attribute records the
default value for the element represented by the method_info structure. Each
method_info structures representing an element of an annotation types may contain
at most one AnnotationDefault attribute. The JVM must make this default value
available so it can be applied by appropriate reflective APIs.
The AnnotationDefault attribute has the following format:
AnnotationDefault_attribute {
u2 attribute_name_index;
u4 attribute_length;
element_value default_value;
}
The items of the AnnotationDefault structure are as follows:
- attribute_name_index
- The value of the attribute_name_index item must be a valid index into the
constant_pool table. The constant_pool entry at that index must be a
CONSTANT_Utf8_info structure representing the string "AnnotationDefault".
- attribute_length
- The value of the attribute_length item indicates the length of the attribute,
excluding the initial six bytes. The value of the attribute_length item is
thus dependent on the default value.
- default_value
- The default_value item represents the default value of the annotation type
element
whose default
value is represented by this AnnotationDefault attribute.
- Author:
- Eugene Kuleshov
- See Also:
- JSR 175 : A Metadata
Facility for the Java Programming Language
Method Summary |
protected Attribute |
read(ClassReader cr,
int off,
int len,
char[] buf,
int codeOff,
Label[] labels)
Reads a type attribute. |
String |
toString()
Returns value in the format described in JSR-175 for Java source code. |
protected ByteVector |
write(ClassWriter cw,
byte[] code,
int len,
int maxStack,
int maxLocals)
Returns the byte array form of this attribute. |
defaultValue
public Object defaultValue
- Default value for annotation. Could be one of
Byte
, Character
, Double
,
Float
, Integer
, Long
, Short
,
Boolean
, String
,
Annotation.EnumConstValue
, Type
,
Annotation
or Object[]
.
AnnotationDefaultAttribute
public AnnotationDefaultAttribute()
AnnotationDefaultAttribute
public AnnotationDefaultAttribute(Object defaultValue)
read
protected Attribute read(ClassReader cr,
int off,
int len,
char[] buf,
int codeOff,
Label[] labels)
- Description copied from class:
Attribute
- Reads a
type
attribute. This method must return a new
Attribute
object, of type type
, corresponding to the
len bytes starting at the given offset, in the given class reader.
- Overrides:
read
in class Attribute
- Parameters:
cr
- the class that contains the attribute to be read.off
- index of the first byte of the attribute's content in cr.b
. The 6 attribute header bytes, containing the type
and the length of the attribute, are not taken into account here.len
- the length of the attribute's content.buf
- buffer to be used to call readUTF8
,
readClass
or readConst
.codeOff
- index of the first byte of code's attribute content in
cr.b
, or -1 if the attribute to be read is not a
code attribute. The 6 attribute header bytes, containing the type and
the length of the attribute, are not taken into account here.labels
- the labels of the method's code, or null if the
attribute to be read is not a code attribute.
- Returns:
- a new
Attribute
object corresponding to the given
bytes.
write
protected ByteVector write(ClassWriter cw,
byte[] code,
int len,
int maxStack,
int maxLocals)
- Description copied from class:
Attribute
- Returns the byte array form of this attribute.
- Overrides:
write
in class Attribute
- Parameters:
cw
- the class to which this attribute must be added. This parameter
can be used to add to the constant pool of this class the items that
corresponds to this attribute.code
- the bytecode of the method corresponding to this code
attribute, or null if this attribute is not a code
attributes.len
- the length of the bytecode of the method corresponding to this
code attribute, or null if this attribute is not a code
attribute.maxStack
- the maximum stack size of the method corresponding to this
code attribute, or -1 if this attribute is not a code attribute.maxLocals
- the maximum number of local variables of the method
corresponding to this code attribute, or -1 if this attribute is not
a code attribute.
- Returns:
- the byte array form of this attribute.
toString
public String toString()
- Returns value in the format described in JSR-175 for Java source code.
- Overrides:
toString
in class Object
- Returns:
- value in the format described in JSR-175 for Java source code.