com.vladium.jcd.cls.attribute

类 CodeAttribute_info

java.lang.Object

com.vladium.jcd.cls.attribute.Attribute_info

com.vladium.jcd.cls.attribute.CodeAttribute_info

所有已实现的接口:

IClassFormatOutput, Cloneable

public final class CodeAttribute_info
extends Attribute_info

The Code attribute is a variable-length attribute used in the attributes table of Method_info structures. A Code attribute contains the JVM instructions and auxiliary information for a single Java method, instance initialization method, or class or interface initialization method. Every Java Virtual Machine implementation must recognize Code attributes. There must be exactly one Code attribute in each method_info structure.

The Code attribute has the format

  Code_attribute {
          u2 attribute_name_index;
          u4 attribute_length;
          u2 max_stack;
          u2 max_locals;
          u4 code_length;
          u1 code[code_length];
          u2 exception_table_length;
          {            u2 start_pc;
                        u2 end_pc;
                        u2  handler_pc;
                        u2  catch_type;
          }        exception_table[exception_table_length];

          u2 attributes_count;
          attribute_info attributes[attributes_count];
  }
 

The value of the max_stack item gives the maximum number of words on the operand stack at any point during execution of this method.

The value of the max_locals item gives the number of local variables used by this method, including the parameters passed to the method on invocation. The index of the first local variable is 0 . The greatest local variable index for a one-word value is max_locals-1 . The greatest local variable index for a two-word value is max_locals-2.

The value of the code_length item gives the number of bytes in the code array for this method. The value of code_length must be greater than zero; the code array must not be empty.The code array gives the actual bytes of Java Virtual Machine code that implement the method.

The value of the exception_table_length item gives the number of entries in the exception_table table. Each entry in the exception_table array describes one exception handler in the code array: see Exception_info.

The value of the attributes_count item indicates the number of attributes of the Code attribute. Each value of the attributes table must be a variable-length attribute structure. A Code attribute can have any number of optional attributes associated with it.

作者:

(C) 2001, Vlad Roubtsov

字段概要

字段

限定符和类型	字段和说明
static byte[]	EMPTY_BYTE_ARRAY
int	m_max_locals
int	m_max_stack

从类继承的字段 com.vladium.jcd.cls.attribute.Attribute_info

ATTRIBUTE_BRIDGE, ATTRIBUTE_CODE, ATTRIBUTE_CONSTANT_VALUE, ATTRIBUTE_EXCEPTIONS, ATTRIBUTE_INNERCLASSES, ATTRIBUTE_LINE_NUMBER_TABLE, ATTRIBUTE_SOURCEFILE, ATTRIBUTE_SYNTHETIC, m_attribute_length, m_name_index

构造器概要

构造器

构造器和说明
CodeAttribute_info(int attribute_name_index, int max_stack, int max_locals, byte[] code, IExceptionHandlerTable exceptionHandlerTable, IAttributeCollection attributes)

方法概要

限定符和类型	方法和说明
void	accept(IAttributeVisitor visitor, Object ctx)
Object	clone() Performs a deep copy.
IAttributeCollection	getAttributes()
byte[]	getCode() NOTE: must also use getCodeSize()
int	getCodeSize()
IExceptionHandlerTable	getExceptionTable()
long	length() Returns the total length of this attribute when converted to .class format [including the 6-byte header]
void	setCode(byte[] code, int codeSize)
String	toString()
void	writeInClassFormat(UDataOutputStream out)

从类继承的方法 com.vladium.jcd.cls.attribute.Attribute_info

getName, new_Attribute_info

从类继承的方法 java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

字段详细资料

EMPTY_BYTE_ARRAY

public static final byte[] EMPTY_BYTE_ARRAY

m_max_stack

public int m_max_stack

m_max_locals

public int m_max_locals

构造器详细资料

CodeAttribute_info

public CodeAttribute_info(int attribute_name_index,
                          int max_stack,
                          int max_locals,
                          byte[] code,
                          IExceptionHandlerTable exceptionHandlerTable,
                          IAttributeCollection attributes)

方法详细资料

getCode

public final byte[] getCode()

NOTE: must also use getCodeSize()

返回:

getCodeSize

public final int getCodeSize()

getAttributes

public IAttributeCollection getAttributes()

getExceptionTable

public IExceptionHandlerTable getExceptionTable()

length

public long length()

从类复制的说明: Attribute_info

Returns the total length of this attribute when converted to .class format [including the 6-byte header]

指定者:

length 在类中 Attribute_info

accept

public void accept(IAttributeVisitor visitor,
                   Object ctx)

指定者:

accept 在类中 Attribute_info

toString

public String toString()

指定者:

toString 在类中 Attribute_info

clone

public Object clone()

Performs a deep copy.

覆盖:

clone 在类中 Attribute_info

writeInClassFormat

public void writeInClassFormat(UDataOutputStream out)
                        throws IOException

指定者:

writeInClassFormat 在接口中 IClassFormatOutput

覆盖:

writeInClassFormat 在类中 Attribute_info

抛出:

IOException

setCode

public void setCode(byte[] code,
                    int codeSize)