Class MethodEditor

java.lang.Object
EDU.purdue.cs.bloat.editor.MethodEditor
All Implemented Interfaces:
Opcode
public class MethodEditor extends Object implements Opcode
MethodEditor provides a means to edit a method of a class. A MethodEditor gathers information from a MethodInfo object. It then goes through the bytecodes of the method and extracts information about the method. Along the way it creates an array of Instruction and Label objects that represent the code. Additionally, it models the try-catch blocks in the method and their associated exception handlers.
See Also:

  • Field Details

    • PRESERVE_DEBUG

      public static boolean PRESERVE_DEBUG

    • UNIQUE_HANDLERS

      public static boolean UNIQUE_HANDLERS

    • OPT_STACK_2

      public static boolean OPT_STACK_2

    • uMap

      public UseMap uMap

  • Constructor Details

    • MethodEditor

      public MethodEditor(ClassEditor editor, int modifiers, Class returnType, String methodName, Class[] paramTypes, Class[] exceptionTypes)

    • MethodEditor

      public MethodEditor(ClassEditor editor, int modifiers, Type returnType, String methodName, Type[] paramTypes, Type[] exceptionTypes)
      Creates a new MethodEditor for editing a method in a given class with the given modifiers, return type, name, parameter types, and exception types.
      Parameters:
      modifiers - The modifiers for the new method
      returnType - The return type of the method. If, returnType is null, the return type is assumed to be void.
      methodName - The name of the method
      paramTypes - The types of the parameters to the new method. If paramTypes is null, then we assume that there are no arguments.
      exceptionTypes - The types of exceptions that may be thrown by the new method. If exceptionTypes is null, then we assume that no exceptions are declared.

    • MethodEditor

      public MethodEditor(ClassEditor editor, MethodInfo methodInfo)
      Constructor.
      Parameters:
      editor - The class containing the method.
      methodInfo - The method to edit.
      See Also:

  • Method Details

    • exceptions

      public Type[] exceptions()
      Returns the Types of exceptions that this method may throw.

    • isDirty

      public boolean isDirty()
      Returns true if this method has been modified.

    • setDirty

      public void setDirty(boolean dirty)
      Sets the dirty flag of this method. The dirty flag is true if the method has been modified.

    • delete

      public void delete()
      Marks this method for deletion. Once a method has been marked for deletion all attempts to change it will throw an IllegalStateException.

    • paramTypes

      public Type[] paramTypes()
      Returns an array of Types representing the types of the parameters of this method. It's really used to figure out the type of the local variables that hold the parameters. So, wide data is succeeded by an empty slot. Also, for virtual methods, the first element in the array is the receiver.

    • paramAt

      public LocalVariable paramAt(int index)
      Get the LocalVariable for the parameter at the given index.
      Parameters:
      index - The index into the params (0 is the this pointer or the first argument, if static).
      Returns:
      The LocalVariable for the parameter at the given index.

    • methodInfo

      public MethodInfo methodInfo()
      Returns the raw MethodInfo of the method being edited.

    • declaringClass

      public ClassEditor declaringClass()
      Returns the class which declared the method.

    • maxLocals

      public int maxLocals()
      Returns the maximum number of locals used by the method.

    • isPublic

      public boolean isPublic()

    • isPrivate

      public boolean isPrivate()

    • isProtected

      public boolean isProtected()

    • isPackage

      public boolean isPackage()
      Returns true is the method has package level visibility

    • isStatic

      public boolean isStatic()

    • isFinal

      public boolean isFinal()

    • isSynchronized

      public boolean isSynchronized()

    • isNative

      public boolean isNative()

    • isAbstract

      public boolean isAbstract()

    • isInterface

      public boolean isInterface()
      Returns true if this method's class is an interface.

    • setPublic

      public void setPublic(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setPrivate

      public void setPrivate(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setProtected

      public void setProtected(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setStatic

      public void setStatic(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setFinal

      public void setFinal(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setSynchronized

      public void setSynchronized(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setNative

      public void setNative(boolean flag)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • setAbstract

      public void setAbstract(boolean flag)

    • clearCode

      public void clearCode()
      Remove all the instructions in preparation for the instructions being added back after a control flow graph edit.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • clearCode2

      public void clearCode2()
      Like clear code, but doesn't reset the maxLocals. I'm not really sure why this works, but it stops certain parts of code that is generated and then re-cfg'd from being eliminated as dead

    • name

      public String name()
      Returns the name of the method.

    • isConstructor

      public boolean isConstructor()
      Returns true if the method being edited is a constructor.

    • type

      public Type type()
      Returns the type of the method.

    • nameAndType

      public NameAndType nameAndType()
      Returns the NameAndType of the method.

    • memberRef

      public MemberRef memberRef()
      Returns a MemberRef for the method.

    • codeLength

      public int codeLength()
      Get the length of the code array.
      Returns:
      The length of the code array.

    • setCode

      public void setCode(List v)
      Throws:
      IllegalStateException - This field has been marked for deletion

    • code

      public List code()
      Returns the code (Instructions and Labels) in the method.

    • firstBlock

      public Label firstBlock()
      Get the label of the first block.

    • nextBlock

      public Label nextBlock(Label label)
      Get the label of the next block after the parameter.
      Parameters:
      label - The label at which to begin.
      Returns:
      The label.

    • removeCodeAt

      public void removeCodeAt(int i)
      Removes a Label or Instruction from the code array.
      Parameters:
      i - The index of the element to remove.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • insertCodeAt

      public void insertCodeAt(Object obj, int i)
      Inserts a Label or Instruction into the code array.
      Parameters:
      i - The index of the element to insert before.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • replaceCodeAt

      public void replaceCodeAt(Object obj, int i)
      Replace a Label or Instruction in the code array.
      Parameters:
      obj - The new element.
      i - The index of the element to replace
      Throws:
      IllegalStateException - This field has been marked for deletion

    • codeElementAt

      public Object codeElementAt(int i)
      Returns a Label or Instruction in the code array.
      Parameters:
      i - The index into the code array.
      Returns:
      The element at the index.

    • addLineNumberEntry

      public void addLineNumberEntry(Label label, int lineNumber)
      Add a line number entry.
      Parameters:
      label - The label beginning the range of instructions for this line number.
      lineNumber - The line number.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • numTryCatches

      public int numTryCatches()
      Returns the number of exception handlers in the method.

    • tryCatches

      public Collection tryCatches()
      Returns the exception handlers (TryCatch) in the method.

    • addTryCatch

      public void addTryCatch(TryCatch tryCatch)
      Add an exception handler.
      Parameters:
      tryCatch - An exception handler.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • newLocal

      public LocalVariable newLocal(Type type)
      Creates a new local variable.

    • newLocal

      public LocalVariable newLocal(boolean isWide)
      Creates a new local variable of an undertermined type.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • localAt

      public LocalVariable localAt(int index)
      Returns the LocalVariable with the given index. If there is no local variable at that index, a new one is created at that index. We assume that this variable is not wide.

    • addInstruction

      public void addInstruction(int opcodeClass)
      Add an instruction.
      Parameters:
      opcodeClass - The instruction to add.

    • addInstruction

      public void addInstruction(int opcodeClass, Object operand)
      Add an instruction.
      Parameters:
      opcodeClass - The instruction to add.

    • addInstruction

      public void addInstruction(Instruction inst)
      Add an instruction to the end of the code array.
      Parameters:
      inst - The instruction to add.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • newLabel

      public Label newLabel()
      Get the next available label. That is the Label after the final Instruction in the code array.
      Returns:
      A new label.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • newLabelTrue

      public Label newLabelTrue()

    • addLabel

      public void addLabel(Label label)
      Add a label to the code array to the end of the code array.
      Parameters:
      label - The label to add.
      Throws:
      IllegalStateException - This field has been marked for deletion

    • commit

      public void commit()
      Commits changes made to this MethodEditor back to the MethodInfo on which it is based. Note that committal will take place regardless of whether or not the method is dirty.

    • print

      public void print(PrintStream out)
      Print the method.
      Parameters:
      out - Stream to which to print.

    • equals

      public boolean equals(Object o)
      Two MethodEditors are equal if they edit the same method in the same class.
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      A MethodEditor's hash code is based on the hash codes for its class, name, and type.
      Overrides:
      hashCode in class Object

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • uMap

      public UseMap uMap()

    • rememberDef

      public void rememberDef(LocalExpr e)