CtBehavior (Javassist API)

java.lang.Object
- javassist.CtMember
- - javassist.CtBehavior

Direct Known Subclasses:

CtConstructor, CtMethod
```
public abstract class CtBehavior
extends CtMember
```
CtBehavior represents a method, a constructor, or a static constructor (class initializer). It is the abstract super class of CtMethod and CtConstructor.
To directly read or modify bytecode, obtain MethodInfo objects.

See Also:

getMethodInfo()

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`addCatch(java.lang.String src, CtClass exceptionType)` Adds a catch clause that handles an exception thrown in the body.
`void`	`addCatch(java.lang.String src, CtClass exceptionType, java.lang.String exceptionName)` Adds a catch clause that handles an exception thrown in the body.
`void`	`addLocalVariable(java.lang.String name, CtClass type)` Declares a new local variable.
`void`	`addParameter(CtClass type)` Appends a new parameter, which becomes the last parameter.
`java.lang.Object`	`getAnnotation(java.lang.Class clz)` Returns the annotation if the class has the specified annotation class.
`java.lang.Object[]`	`getAnnotations()` Returns the annotations associated with this method or constructor.
`byte[]`	`getAttribute(java.lang.String name)` Obtains an attribute with the given name.
`java.lang.Object[]`	`getAvailableAnnotations()` Returns the annotations associated with this method or constructor.
`java.lang.Object[][]`	`getAvailableParameterAnnotations()` Returns the parameter annotations associated with this method or constructor.
`CtClass[]`	`getExceptionTypes()` Obtains exceptions that this method/constructor may throw.
`java.lang.String`	`getGenericSignature()` Returns the generic signature of the method.
`abstract java.lang.String`	`getLongName()` Returns the method or constructor name followed by parameter types such as `javassist.CtBehavior.stBody(String)`.
`MethodInfo`	`getMethodInfo()` Returns the `MethodInfo` representing this method/constructor in the class file.
`MethodInfo`	`getMethodInfo2()` Returns the `MethodInfo` representing the method/constructor in the class file (read only).
`int`	`getModifiers()` Obtains the modifiers of the method/constructor.
`java.lang.Object[][]`	`getParameterAnnotations()` Returns the parameter annotations associated with this method or constructor.
`CtClass[]`	`getParameterTypes()` Obtains parameter types of this method/constructor.
`java.lang.String`	`getSignature()` Returns the method signature (the parameter types and the return type).
`boolean`	`hasAnnotation(java.lang.String typeName)` Returns true if the class has the specified annotation type.
`void`	`insertAfter(java.lang.String src)` Inserts bytecode at the end of the body.
`void`	`insertAfter(java.lang.String src, boolean asFinally)` Inserts bytecode at the end of the body.
`int`	`insertAt(int lineNum, boolean modify, java.lang.String src)` Inserts bytecode at the specified line in the body.
`int`	`insertAt(int lineNum, java.lang.String src)` Inserts bytecode at the specified line in the body.
`void`	`insertBefore(java.lang.String src)` Inserts bytecode at the beginning of the body.
`void`	`insertParameter(CtClass type)` Inserts a new parameter, which becomes the first parameter.
`void`	`instrument(CodeConverter converter)` Modifies the method/constructor body.
`void`	`instrument(ExprEditor editor)` Modifies the method/constructor body.
`abstract boolean`	`isEmpty()` Returns true if the body is empty.
`void`	`setAttribute(java.lang.String name, byte[] data)` Adds an attribute.
`void`	`setBody(java.lang.String src)` Sets a method/constructor body.
`void`	`setBody(java.lang.String src, java.lang.String delegateObj, java.lang.String delegateMethod)` Sets a method/constructor body.
`void`	`setExceptionTypes(CtClass[] types)` Sets exceptions that this method/constructor may throw.
`void`	`setGenericSignature(java.lang.String sig)` Set the generic signature of the method.
`void`	`setModifiers(int mod)` Sets the encoded modifiers of the method/constructor.
`void`	`useCflow(java.lang.String name)` Declares to use `$cflow` for this method/constructor.

Methods inherited from class javassist.CtMember
getDeclaringClass, getName, hasAnnotation, toString, visibleFrom

Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Method Detail
  - getLongName
```
public abstract java.lang.String getLongName()
```
    Returns the method or constructor name followed by parameter types such as javassist.CtBehavior.stBody(String).
    
    Since:
    
    3.5
  - getMethodInfo
```
public MethodInfo getMethodInfo()
```
    Returns the MethodInfo representing this method/constructor in the class file.
    If you modify the bytecode through the returned MethodInfo object, you might have to explicitly rebuild a stack map table. Javassist does not automatically rebuild it for avoiding unnecessary rebuilding.
    
    See Also:
    
    MethodInfo.rebuildStackMap(ClassPool)
  - getMethodInfo2
```
public MethodInfo getMethodInfo2()
```
    Returns the MethodInfo representing the method/constructor in the class file (read only). Normal applications do not need calling this method. Use getMethodInfo().
    The MethodInfo object obtained by this method is read only. Changes to this object might not be reflected on a class file generated by toBytecode(), toClass(), etc in CtClass.
    This method is available even if the CtClass containing this method is frozen. However, if the class is frozen, the MethodInfo might be also pruned.
    
    See Also:
    
    getMethodInfo(), CtClass.isFrozen(), CtClass.prune()
  - getModifiers
```
public int getModifiers()
```
    Obtains the modifiers of the method/constructor.
    
    Specified by:
    
    getModifiers in class CtMember
    
    Returns:
    
    modifiers encoded with javassist.Modifier.
    
    See Also:
    
    Modifier
  - setModifiers
```
public void setModifiers(int mod)
```
    Sets the encoded modifiers of the method/constructor.
    Changing the modifiers may cause a problem. For example, if a non-static method is changed to static, the method will be rejected by the bytecode verifier.
    
    Specified by:
    
    setModifiers in class CtMember
    
    See Also:
    
    Modifier
  - hasAnnotation
```
public boolean hasAnnotation(java.lang.String typeName)
```
    Returns true if the class has the specified annotation type.
    
    Specified by:
    
    hasAnnotation in class CtMember
    
    Parameters:
    
    typeName - the name of annotation type.
    
    Returns:
    
    true if the annotation is found, otherwise false.
    
    Since:
    
    3.21
  - getAnnotation
```
public java.lang.Object getAnnotation(java.lang.Class clz)
                               throws java.lang.ClassNotFoundException
```
    Returns the annotation if the class has the specified annotation class. For example, if an annotation @Author is associated with this method/constructor, an Author object is returned. The member values can be obtained by calling methods on the Author object.
    
    Specified by:
    
    getAnnotation in class CtMember
    
    Parameters:
    
    clz - the annotation class.
    
    Returns:
    
    the annotation if found, otherwise null.
    
    Throws:
    
    java.lang.ClassNotFoundException
    
    Since:
    
    3.11
  - getAnnotations
```
public java.lang.Object[] getAnnotations()
                                  throws java.lang.ClassNotFoundException
```
    Returns the annotations associated with this method or constructor.
    
    Specified by:
    
    getAnnotations in class CtMember
    
    Returns:
    
    an array of annotation-type objects.
    
    Throws:
    
    java.lang.ClassNotFoundException
    
    Since:
    
    3.1
    
    See Also:
    
    getAvailableAnnotations()
  - getAvailableAnnotations
```
public java.lang.Object[] getAvailableAnnotations()
```
    Returns the annotations associated with this method or constructor. If any annotations are not on the classpath, they are not included in the returned array.
    
    Specified by:
    
    getAvailableAnnotations in class CtMember
    
    Returns:
    
    an array of annotation-type objects.
    
    Since:
    
    3.3
    
    See Also:
    
    getAnnotations()
  - getParameterAnnotations
```
public java.lang.Object[][] getParameterAnnotations()
                                             throws java.lang.ClassNotFoundException
```
    Returns the parameter annotations associated with this method or constructor.
    
    Returns:
    
    an array of annotation-type objects. The length of the returned array is equal to the number of the formal parameters. If each parameter has no annotation, the elements of the returned array are empty arrays.
    
    Throws:
    
    java.lang.ClassNotFoundException
    
    Since:
    
    3.1
    
    See Also:
    
    getAvailableParameterAnnotations(), getAnnotations()
  - getAvailableParameterAnnotations
```
public java.lang.Object[][] getAvailableParameterAnnotations()
```
    Returns the parameter annotations associated with this method or constructor. If any annotations are not on the classpath, they are not included in the returned array.
    
    Returns:
    
    an array of annotation-type objects. The length of the returned array is equal to the number of the formal parameters. If each parameter has no annotation, the elements of the returned array are empty arrays.
    
    Since:
    
    3.3
    
    See Also:
    
    getParameterAnnotations(), getAvailableAnnotations()
  - getParameterTypes
```
public CtClass[] getParameterTypes()
                            throws NotFoundException
```
    Obtains parameter types of this method/constructor.
    
    Throws:
    
    NotFoundException
  - getSignature
```
public java.lang.String getSignature()
```
    Returns the method signature (the parameter types and the return type). The method signature is represented by a character string called method descriptor, which is defined in the JVM specification. If two methods/constructors have the same parameter types and the return type, getSignature() returns the same string (the return type of constructors is void).
    Note that the returned string is not the type signature contained in the SignatureAttirbute. It is a descriptor.
    
    Specified by:
    
    getSignature in class CtMember
    
    See Also:
    
    Descriptor, getGenericSignature()
  - getGenericSignature
```
public java.lang.String getGenericSignature()
```
    Returns the generic signature of the method. It represents parameter types including type variables.
    
    Specified by:
    
    getGenericSignature in class CtMember
    
    Since:
    
    3.17
    
    See Also:
    
    SignatureAttribute.toMethodSignature(String)
  - setGenericSignature
```
public void setGenericSignature(java.lang.String sig)
```
    Set the generic signature of the method. It represents parameter types including type variables. See CtClass.setGenericSignature(String) for a code sample.
    
    Specified by:
    
    setGenericSignature in class CtMember
    
    Parameters:
    
    sig - a new generic signature.
    
    Since:
    
    3.17
    
    See Also:
    
    SignatureAttribute.MethodSignature.encode()
  - getExceptionTypes
```
public CtClass[] getExceptionTypes()
                            throws NotFoundException
```
    Obtains exceptions that this method/constructor may throw.
    
    Returns:
    
    a zero-length array if there is no throws clause.
    
    Throws:
    
    NotFoundException
  - setExceptionTypes
```
public void setExceptionTypes(CtClass[] types)
                       throws NotFoundException
```
    Sets exceptions that this method/constructor may throw.
    
    Throws:
    
    NotFoundException
  - isEmpty
```
public abstract boolean isEmpty()
```
    Returns true if the body is empty.
  - setBody
```
public void setBody(java.lang.String src)
             throws CannotCompileException
```
    Sets a method/constructor body.
    
    Parameters:
    
    src - the source code representing the body. It must be a single statement or block. If it is null, the substituted body does nothing except returning zero or null.
    
    Throws:
    
    CannotCompileException
  - setBody
```
public void setBody(java.lang.String src,
                    java.lang.String delegateObj,
                    java.lang.String delegateMethod)
             throws CannotCompileException
```
    Sets a method/constructor body.
    
    Parameters:
    
    src - the source code representing the body. It must be a single statement or block. If it is null, the substituted body does nothing except returning zero or null.
    
    delegateObj - the source text specifying the object that is called on by $proceed().
    
    delegateMethod - the name of the method that is called by $proceed().
    
    Throws:
    
    CannotCompileException
  - getAttribute
```
public byte[] getAttribute(java.lang.String name)
```
    Obtains an attribute with the given name. If that attribute is not found in the class file, this method returns null.
    Note that an attribute is a data block specified by the class file format. It is not an annotation. See AttributeInfo.
    
    Specified by:
    
    getAttribute in class CtMember
    
    Parameters:
    
    name - attribute name
  - setAttribute
```
public void setAttribute(java.lang.String name,
                         byte[] data)
```
    Adds an attribute. The attribute is saved in the class file.
    Note that an attribute is a data block specified by the class file format. It is not an annotation. See AttributeInfo.
    
    Specified by:
    
    setAttribute in class CtMember
    
    Parameters:
    
    name - attribute name
    
    data - attribute value
  - useCflow
```
public void useCflow(java.lang.String name)
              throws CannotCompileException
```
    Declares to use $cflow for this method/constructor. If $cflow is used, the class files modified with Javassist requires a support class javassist.runtime.Cflow at runtime (other Javassist classes are not required at runtime).
    Every $cflow variable is given a unique name. For example, if the given name is "Point.paint", then the variable is indicated by $cflow(Point.paint).
    
    Parameters:
    
    name - $cflow name. It can include alphabets, numbers, _, $, and . (dot).
    
    Throws:
    
    CannotCompileException
    
    See Also:
    
    Cflow
  - addLocalVariable
```
public void addLocalVariable(java.lang.String name,
                             CtClass type)
                      throws CannotCompileException
```
    Declares a new local variable. The scope of this variable is the whole method body. The initial value of that variable is not set. The declared variable can be accessed in the code snippet inserted by insertBefore(), insertAfter(), etc.
    If the second parameter asFinally to insertAfter() is true, the declared local variable is not visible from the code inserted by insertAfter().
    
    Parameters:
    
    name - the name of the variable
    
    type - the type of the variable
    
    Throws:
    
    CannotCompileException
    
    See Also:
    
    insertBefore(String), insertAfter(String)
  - insertParameter
```
public void insertParameter(CtClass type)
                     throws CannotCompileException
```
    Inserts a new parameter, which becomes the first parameter.
    
    Throws:
    
    CannotCompileException
  - addParameter
```
public void addParameter(CtClass type)
                  throws CannotCompileException
```
    Appends a new parameter, which becomes the last parameter.
    
    Throws:
    
    CannotCompileException
  - instrument
```
public void instrument(CodeConverter converter)
                throws CannotCompileException
```
    Modifies the method/constructor body.
    
    Parameters:
    
    converter - specifies how to modify.
    
    Throws:
    
    CannotCompileException
  - instrument
```
public void instrument(ExprEditor editor)
                throws CannotCompileException
```
    Modifies the method/constructor body.
    While executing this method, only replace() in Expr is available for bytecode modification. Other methods such as insertBefore() may collapse the bytecode because the ExprEditor loses its current position.
    
    Parameters:
    
    editor - specifies how to modify.
    
    Throws:
    
    CannotCompileException
    
    See Also:
    
    Expr.replace(String), insertBefore(String)
  - insertBefore
```
public void insertBefore(java.lang.String src)
                  throws CannotCompileException
```
    Inserts bytecode at the beginning of the body.
    If this object represents a constructor, the bytecode is inserted before a constructor in the super class or this class is called. Therefore, the inserted bytecode is subject to constraints described in Section 4.8.2 of The Java Virtual Machine Specification (2nd ed). For example, it cannot access instance fields or methods although it may assign a value to an instance field directly declared in this class. Accessing static fields and methods is allowed. Use insertBeforeBody() in CtConstructor.
    
    Parameters:
    
    src - the source code representing the inserted bytecode. It must be a single statement or block.
    
    Throws:
    
    CannotCompileException
    
    See Also:
    
    CtConstructor.insertBeforeBody(String)
  - insertAfter
```
public void insertAfter(java.lang.String src)
                 throws CannotCompileException
```
    Inserts bytecode at the end of the body. The bytecode is inserted just before every return insturction. It is not executed when an exception is thrown.
    
    Parameters:
    
    src - the source code representing the inserted bytecode. It must be a single statement or block.
    
    Throws:
    
    CannotCompileException
  - insertAfter
```
public void insertAfter(java.lang.String src,
                        boolean asFinally)
                 throws CannotCompileException
```
    Inserts bytecode at the end of the body. The bytecode is inserted just before every return insturction.
    
    Parameters:
    
    src - the source code representing the inserted bytecode. It must be a single statement or block.
    
    asFinally - true if the inserted bytecode is executed not only when the control normally returns but also when an exception is thrown. If this parameter is true, the inserted code cannot access local variables.
    
    Throws:
    
    CannotCompileException
  - addCatch
```
public void addCatch(java.lang.String src,
                     CtClass exceptionType)
              throws CannotCompileException
```
    Adds a catch clause that handles an exception thrown in the body. The catch clause must end with a return or throw statement.
    
    Parameters:
    
    src - the source code representing the catch clause. It must be a single statement or block.
    
    exceptionType - the type of the exception handled by the catch clause.
    
    Throws:
    
    CannotCompileException
  - addCatch
```
public void addCatch(java.lang.String src,
                     CtClass exceptionType,
                     java.lang.String exceptionName)
              throws CannotCompileException
```
    Adds a catch clause that handles an exception thrown in the body. The catch clause must end with a return or throw statement.
    
    Parameters:
    
    src - the source code representing the catch clause. It must be a single statement or block.
    
    exceptionType - the type of the exception handled by the catch clause.
    
    exceptionName - the name of the variable containing the caught exception, for example, $e.
    
    Throws:
    
    CannotCompileException
  - insertAt
```
public int insertAt(int lineNum,
                    java.lang.String src)
             throws CannotCompileException
```
    Inserts bytecode at the specified line in the body. It is equivalent to:
    insertAt(lineNum, true, src)
    See this method as well.
    
    Parameters:
    
    lineNum - the line number. The bytecode is inserted at the beginning of the code at the line specified by this line number.
    
    src - the source code representing the inserted bytecode. It must be a single statement or block.
    
    Returns:
    
    the line number at which the bytecode has been inserted.
    
    Throws:
    
    CannotCompileException
    
    See Also:
    
    insertAt(int,boolean,String)
  - insertAt
```
public int insertAt(int lineNum,
                    boolean modify,
                    java.lang.String src)
             throws CannotCompileException
```
    Inserts bytecode at the specified line in the body.
    If there is not a statement at the specified line, the bytecode might be inserted at the line including the first statement after that line specified. For example, if there is only a closing brace at that line, the bytecode would be inserted at another line below. To know exactly where the bytecode will be inserted, call with modify set to false.
    
    Parameters:
    
    lineNum - the line number. The bytecode is inserted at the beginning of the code at the line specified by this line number.
    
    modify - if false, this method does not insert the bytecode. It instead only returns the line number at which the bytecode would be inserted.
    
    src - the source code representing the inserted bytecode. It must be a single statement or block. If modify is false, the value of src can be null.
    
    Returns:
    
    the line number at which the bytecode has been inserted.
    
    Throws:
    
    CannotCompileException

Class CtBehavior

Method Summary

Methods inherited from class javassist.CtMember

Methods inherited from class java.lang.Object

Method Detail

getLongName

getMethodInfo

getMethodInfo2

getModifiers

setModifiers

hasAnnotation

getAnnotation

getAnnotations

getAvailableAnnotations

getParameterAnnotations

getAvailableParameterAnnotations

getParameterTypes

getSignature

getGenericSignature

setGenericSignature

getExceptionTypes

setExceptionTypes

isEmpty

setBody

setBody

getAttribute

setAttribute

useCflow

addLocalVariable

insertParameter

addParameter

instrument

instrument

insertBefore

insertAfter

insertAfter

addCatch

addCatch

insertAt

insertAt