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JDK 5 Documentation v1.4.1, Java 2 SDK 英文文档
SourceDebugExtension Class File Attribute - JDK 5 Documentation v1.4.1, Java 2 SDK 英文文档
SourceDebugExtension Class File Attribute
Java virtual machine class file attributes are described in
section
4.7
of the
The Java
Virtual Machine Specification.
The definition of the added attribute is in the context of
The Java Virtual Machine Specification:
The SourceDebugExtension attribute is an optional attribute in the
attributes
table of the ClassFile structure. There can be no more than one
SourceDebugExtension attribute in the attributes table of a given
ClassFile structure.
The SourceDebugExtension attribute has the following format:
SourceDebugExtension_attribute {
u2 attribute_name_index;
u4 attribute_length;
u1 debug_extension[attribute_length];
}
The items of the SourceDebugExtension_attribute 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
"SourceDebugExtension" .
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 the number of bytes in
the debug_extension[] item.
debug_extension[]
- The
debug_extension array holds a string, which must be
in UTF-8 format. There is no terminating zero byte.
The string in the debug_extension item will be interpreted as
extended debugging information. The content of this string has no semantic
effect on the Java Virtual Machine.
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