org.jibx.binding.classes
Class ClassFile

java.lang.Object
  org.jibx.binding.classes.ClassFile

public class ClassFile
extends Object

Class file information. Wraps the actual class file data as well as associated management information.

Author:

Dennis M. Sosnoski

Field Summary

protected static byte[]	EMPTY_BYTES
static ClassItem[]	EMPTY_CLASS_ITEMS
protected static ExistingMethod[]	EMPTY_METHOD_ARRAY
protected InstructionBuilder	m_instBuilder Instruction factory for modified class (lazy create, only if needed).
protected String[]	m_interfaceNames Names of all interfaces directly implemented by this class.
protected ClassFile	m_superClass Super class of this class (set by caller, since it may require additional information to find the class file).
static int	PACKAGE_ACCESS
static int	PRIVATE_ACCESS
protected static int	PRIVATEFIELD_ACCESS
static int	PROTECTED_ACCESS
static int	PUBLIC_ACCESS
static int	SYNTHETIC_ACCESS_FLAG

Constructor Summary

ClassFile(String name, File root, ClassFile sclas, int access, String[] impls)
Constructor for new class file.

ClassFile(String name, File root, File file)
Constructor for preexisting class file.

ClassFile(String name, String sig)
Constructor for synthetic placeholder classfile with no backing class data.

Method Summary

protected void	accumulateInterfaces(String[] intfs, HashMap map, ArrayList accs) Accumulate interface signatures recursively.
ClassItem	addDefaultConstructor() Add default constructor to a class.
ClassItem	addField(String type, String name, int access) Add field to class without initialization.
ClassItem	addField(String type, String name, int access, int init) Add field to class with initial int value.
ClassItem	addField(String type, String name, int access, String init) Add field to class with initial String value.
boolean	addInterface(String intf) Add interface to class.
ClassItem	addMethod(org.apache.bcel.classfile.Method method) Add method to class.
ClassItem	addPrivateField(String type, String name) Add private field to class without initialization.
void	codeComplete() Finalize current modified state of class.
protected int	computeHashCode() Computes a hash code based on characteristics of the class.
void	delete() Delete class file information.
boolean	deleteField(String name) Delete field from class.
boolean	deleteMethod(String name, String sig) Delete method from class.
String	deriveClassName(String prefix, String suffix) Derive generated class name.
static boolean	equalFieldOrMethods(org.apache.bcel.classfile.FieldOrMethod a, org.apache.bcel.classfile.FieldOrMethod b) Compare two field or method items to see if they're equal.
static boolean	equalMethods(org.apache.bcel.classfile.Method a, org.apache.bcel.classfile.Method b) Compare two methods to see if they're equal.
boolean	equals(Object obj) Check if objects are equal.
protected org.apache.bcel.classfile.Field	getAccessibleField(String name) Get internal information for field.
protected org.apache.bcel.classfile.Method	getAccessibleMethod(String name, String sig) Get internal information for method without respect to potential trailing arguments or return value.
ClassItem	getBestMethod(String name, String ret, String[] args) Get information for best matching method.
ExistingMethod[]	getBindingMethods(String prefix, String[] matches) Get all binding methods currently defined in class.
static ClassFile	getClassFile(String name) Constructor for preexisting class file from classpath.
static ClassLoader	getClassLoader() Get the classloader used for classes referenced in the binding.
org.apache.bcel.generic.ConstantPoolGen	getConstPoolGen() Get constant pool generator for modifying class.
protected org.apache.bcel.classfile.Field	getDefinedField(String name) Get internal information for field.
ClassItem	getDirectField(String name) Get information for field.
ClassItem	getField(String name) Get information for field.
ClassItem[]	getFieldItems() Get array of fields defined by class.
File	getFile() Get actual file for class.
ClassItem	getInitializerMethod(String sig) Get information for initializer.
String[]	getInstanceSigs() Get signatures for all types of which instances of this type are instances.
InstructionBuilder	getInstructionBuilder() Get instruction builder for modifying class.
String[]	getInterfaces() Get names of all interfaces implemented by class.
ClassItem	getMethod(String name, String sig) Get information for method without respect to potential trailing arguments or return value.
ClassItem	getMethod(String name, String[] sigs) Get information for method matching one of several possible signatures.
ClassItem[]	getMethodItems() Get array of methods defined by class.
String	getName() Get fully qualified class name.
String	getPackage() Get package name.
org.apache.bcel.classfile.JavaClass	getRawClass() Get raw current class information.
File	getRoot() Get root directory for load path.
String	getSignature() Get signature for class as type.
ClassItem	getStaticMethod(String name, String sig) Get information for static method without respect to return value.
ClassFile	getSuperFile() Get superclass information.
String	getSuperName() Get superclass name.
org.apache.bcel.generic.Type	getType() Get class as type.
int	getUseCount() Get use count for class.
int	hashCode() Get hash code.
int	incrementUseCount() Increment use count for class.
boolean	isAbstract() Check if class is abstract.
boolean	isAccessible(ClassItem item) Check accessible method.
boolean	isArray() Check if class is an array.
boolean	isComplete() Check if class is in complete state.
boolean	isImplements(String sig) Check if class implements an interface.
boolean	isInterface() Check if class is an interface.
boolean	isModifiable() Check if class is modifiable.
boolean	isModified() Check if class has been modified.
boolean	isSuperclass(String name) Check if another class is a superclass of this one.
static Class	loadClass(String name) Try loading class from classpath.
String	makeUniqueMethodName(String name) Make method name unique with generated suffix.
void	removeMethod(org.apache.bcel.classfile.Method method) Remove method from class.
void	setModified() Set class modified flag.
static void	setPaths(String[] paths) Set class paths to be searched.
void	setSuperFile(ClassFile sclas) Set superclass information.
void	setUnmodifiable() Force class to unmodifiable state.
ClassItem	updateField(String type, String name, int access, String init) Update class field with initial String value.
void	writeFile() Write out modified class information.
void	writeFile(OutputStream os) Write out modified class information.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Field Detail

PRIVATE_ACCESS

public static final int PRIVATE_ACCESS

See Also:

Constant Field Values

PACKAGE_ACCESS

public static final int PACKAGE_ACCESS

See Also:

Constant Field Values

PROTECTED_ACCESS

public static final int PROTECTED_ACCESS

See Also:

Constant Field Values

PUBLIC_ACCESS

public static final int PUBLIC_ACCESS

See Also:

Constant Field Values

SYNTHETIC_ACCESS_FLAG

public static final int SYNTHETIC_ACCESS_FLAG

See Also:

Constant Field Values

PRIVATEFIELD_ACCESS

protected static final int PRIVATEFIELD_ACCESS

See Also:

Constant Field Values

EMPTY_METHOD_ARRAY

protected static final ExistingMethod[] EMPTY_METHOD_ARRAY

EMPTY_BYTES

protected static final byte[] EMPTY_BYTES

EMPTY_CLASS_ITEMS

public static final ClassItem[] EMPTY_CLASS_ITEMS

m_superClass

protected ClassFile m_superClass

Super class of this class (set by caller, since it may require additional information to find the class file).

m_interfaceNames

protected String[] m_interfaceNames

Names of all interfaces directly implemented by this class.

m_instBuilder

protected InstructionBuilder m_instBuilder

Instruction factory for modified class (lazy create, only if needed).

Constructor Detail

ClassFile

public ClassFile(String name,
                 File root,
                 File file)
          throws IOException,
                 JiBXException

Constructor for preexisting class file. Loads the class data and prepares it for use.

Parameters:

name - fully qualified class name

root - directory root from class loading path list

file - actual class file

Throws:

IOException - if unable to open file

JiBXException - if error in reading class file

ClassFile

public ClassFile(String name,
                 String sig)

Constructor for synthetic placeholder classfile with no backing class data.

Parameters:

name - fully qualified class name

sig - corresponding class signature

ClassFile

public ClassFile(String name,
                 File root,
                 ClassFile sclas,
                 int access,
                 String[] impls)
          throws JiBXException

Constructor for new class file. Initializes the class data and prepares it for use.

Parameters:

name - fully qualified class name

root - directory root from class loading path list

sclas - superclass of new class

access - access flags for class

impls - array of interfaces implemented by new class (non-null, empty if none)

Throws:

JiBXException - on error loading interface information

Method Detail

getClassFile

public static ClassFile getClassFile(String name)
                              throws IOException,
                                     JiBXException

Constructor for preexisting class file from classpath. Loads the class data and prepares it for use.

Parameters:

name - fully qualified class name

Returns:

null if unable to find class file

Throws:

IOException - if error reading file

JiBXException - if error loading superclass or other support file

isInterface

public boolean isInterface()

Check if class is an interface. This only checks existing classes, assuming that no generated classes are interfaces.

Returns:

true if an interface, false if not

isAbstract

public boolean isAbstract()

Check if class is abstract. This only checks existing classes, assuming that no generated classes are abstract.

Returns:

true if an abstract class, false if not

isArray

public boolean isArray()

Check if class is an array. This only checks existing classes, assuming that no generated classes are arrays.

Returns:

true if an array class, false if not

isModifiable

public boolean isModifiable()

Check if class is modifiable.

Returns:

true if class is modifiable, false if not

getName

public String getName()

Get fully qualified class name.

Returns:

fully qualified name for class

getSignature

public String getSignature()

Get signature for class as type.

Returns:

signature for class used as type

getType

public org.apache.bcel.generic.Type getType()

Get class as type.

Returns:

class as type

getPackage

public String getPackage()

Get package name.

Returns:

package name for class

getRoot

public File getRoot()

Get root directory for load path.

Returns:

root directory in path used for loading file

getFile

public File getFile()

Get actual file for class.

Returns:

file used for class

getRawClass

public org.apache.bcel.classfile.JavaClass getRawClass()

Get raw current class information.

Returns:

raw current class information

getSuperName

public String getSuperName()

Get superclass name.

Returns:

fully qualified name of superclass

setSuperFile

public void setSuperFile(ClassFile sclas)

Set superclass information.

Parameters:

sclas - superclass information

getSuperFile

public ClassFile getSuperFile()

Get superclass information.

Returns:

super class information as loaded (null if no superclass - java.lang.Object, interface, or primitive)

getInterfaces

public String[] getInterfaces()

Get names of all interfaces implemented by class.

Returns:

names of all interfaces implemented directly by class (non-null, empty array if none)

addInterface

public boolean addInterface(String intf)

Add interface to class. The interface is added to the class if not already defined.

Parameters:

intf - fully qualified interface name

Returns:

true if added, false if already present

accumulateInterfaces

protected void accumulateInterfaces(String[] intfs,
                                    HashMap map,
                                    ArrayList accs)
                             throws JiBXException

Accumulate interface signatures recursively.

Parameters:

intfs - names of interfaces implemented

map - map for interfaces already accumulated

accs - accumulated interface names

Throws:

JiBXException - if configuration error

getInstanceSigs

public String[] getInstanceSigs()
                         throws JiBXException

Get signatures for all types of which instances of this type are instances.

Returns:

all signatures suppored by instances

Throws:

JiBXException - if configuration error

isImplements

public boolean isImplements(String sig)
                     throws JiBXException

Check if class implements an interface.

Parameters:

sig - signature of interface to be checked

Returns:

true if interface is implemented by class, false if not

Throws:

JiBXException - if configuration error

isSuperclass

public boolean isSuperclass(String name)

Check if another class is a superclass of this one.

Parameters:

name - of superclass to be checked

Returns:

true if named class is a superclass of this one, false if not

getFieldItems

public ClassItem[] getFieldItems()

Get array of fields defined by class.

Returns:

array of fields defined by class

getDefinedField

protected org.apache.bcel.classfile.Field getDefinedField(String name)

Get internal information for field. This can only be used with existing classes, and only checks for fields that are actually members of the class (not superclasses).

Parameters:

name - field name

Returns:

field information, or null if field not found

getAccessibleField

protected org.apache.bcel.classfile.Field getAccessibleField(String name)

Get internal information for field. This can only be used with existing classes. If the field is not found directly, superclasses are checked for inherited fields matching the supplied name.

Parameters:

name - field name

Returns:

field information, or null if field not found

getDirectField

public ClassItem getDirectField(String name)

Get information for field. This can only be used with existing classes, and only checks for fields that are actually members of the class (not superclasses).

Parameters:

name - field name

Returns:

field information, or null if field not found

getField

public ClassItem getField(String name)
                   throws JiBXException

Get information for field. This can only be used with existing classes. If the field is not found directly, superclasses are checked for inherited fields matching the supplied name.

Parameters:

name - field name

Returns:

field information

Throws:

JiBXException - if field not found

getMethodItems

public ClassItem[] getMethodItems()

Get array of methods defined by class.

Returns:

array of methods defined by class

getAccessibleMethod

protected org.apache.bcel.classfile.Method getAccessibleMethod(String name,
                                                               String sig)

Get internal information for method without respect to potential trailing arguments or return value. This can only be used with existing classes. If the method is not found directly, superclasses are checked for inherited methods matching the supplied name. This compares the supplied partial signature against the actual method signature, and considers it a match if the actual sigature starts with the supplied signature..

Parameters:

name - method name

sig - partial method signature to be matched

Returns:

method information, or null if method not found

getMethod

public ClassItem getMethod(String name,
                           String sig)

Get information for method without respect to potential trailing arguments or return value. This can only be used with existing classes. If the method is not found directly, superclasses are checked for inherited methods matching the supplied name. This compares the supplied partial signature against the actual method signature, and considers it a match if the actual sigature starts with the supplied signature..

Parameters:

name - method name

sig - partial method signature to be matched

Returns:

method information, or null if method not found

getMethod

public ClassItem getMethod(String name,
                           String[] sigs)

Get information for method matching one of several possible signatures. This can only be used with existing classes. If a match is not found directly, superclasses are checked for inherited methods matching the supplied name and signatures. The signature variations are checked in the order supplied.

Parameters:

name - method name

sigs - possible signatures for method (including return type)

Returns:

method information, or null if method not found

getBestMethod

public ClassItem getBestMethod(String name,
                               String ret,
                               String[] args)

Get information for best matching method. This tries to find a method which matches the specified name, return type, and argument types. If an exact match is not found it looks for a method with a return type that is extended or implemented by the specified type and arguments that are extended or implemented by the specified types. This can only be used with existing classes. If the method is not found directly, superclasses are checked for inherited methods.

Parameters:

name - method name

ret - return value type (null if indeterminant)

args - argument value types (null if indeterminant)

Returns:

method information, or null if method not found

getInitializerMethod

public ClassItem getInitializerMethod(String sig)

Get information for initializer. This can only be used with existing classes. Only the class itself is checked for an initializer matching the argument list signature.

Parameters:

sig - encoded argument list signature

Returns:

method information, or null if method not found

getStaticMethod

public ClassItem getStaticMethod(String name,
                                 String sig)

Get information for static method without respect to return value. This can only be used with existing classes. Only the class itself is checked for a method matching the supplied name and argument list signature.

Parameters:

name - method name

sig - encoded argument list signature

Returns:

method information, or null if method not found

getBindingMethods

public ExistingMethod[] getBindingMethods(String prefix,
                                          String[] matches)

Get all binding methods currently defined in class. Binding methods are generally identified by a supplied prefix, but additional methods can be specified the the combination of exact name and signature. This is a little kludgy, but necessary to handle the "marshal" method added to mapped classes.

Parameters:

prefix - identifying prefix for binding methods

matches - pairs of method name and signature to be matched as exceptions to the prefix matching

Returns:

existing binding methods

isAccessible

public boolean isAccessible(ClassItem item)

Check accessible method. Check if a field or method in another class is accessible from within this class.

Parameters:

item - field or method information

Returns:

true if accessible, false if not

getConstPoolGen

public org.apache.bcel.generic.ConstantPoolGen getConstPoolGen()

Get constant pool generator for modifying class.

Returns:

constant pool generator for class

getInstructionBuilder

public InstructionBuilder getInstructionBuilder()

Get instruction builder for modifying class.

Returns:

instruction builder for class

addMethod

public ClassItem addMethod(org.apache.bcel.classfile.Method method)

Add method to class.

Parameters:

method - method to be added

Returns:

added method information

removeMethod

public void removeMethod(org.apache.bcel.classfile.Method method)

Remove method from class.

Parameters:

method - method to be removed

addField

public ClassItem addField(String type,
                          String name,
                          int access,
                          String init)

Add field to class with initial String value. If a field with the same name already exists, it is overwritten.

Parameters:

type - fully qualified class name of field type

name - field name

access - access flags for field

init - initial value for field

Returns:

field information

addField

public ClassItem addField(String type,
                          String name,
                          int access,
                          int init)

Add field to class with initial int value. If a field with the same name already exists, it is overwritten.

Parameters:

type - fully qualified class name of field type

name - field name

access - access flags for field

init - initial value for field

Returns:

field information

updateField

public ClassItem updateField(String type,
                             String name,
                             int access,
                             String init)

Update class field with initial String value. If the field already exists with the same characteristics it is left unchanged; otherwise any existing field with the same name is overwritten.

Parameters:

type - fully qualified class name of field type

name - field name

access - access flags for field

init - initial value for field

Returns:

field information

addField

public ClassItem addField(String type,
                          String name,
                          int access)

Add field to class without initialization. If a field with the same name already exists, it is overwritten.

Parameters:

type - fully qualified class name of field type

name - field name

access - access flags for field

Returns:

field information

addPrivateField

public ClassItem addPrivateField(String type,
                                 String name)

Add private field to class without initialization. If a field with the same name already exists, it is overwritten.

Parameters:

type - fully qualified class name of field type

name - field name

Returns:

field information

addDefaultConstructor

public ClassItem addDefaultConstructor()

Add default constructor to a class. The added default constructor just calls the default constructor for the superclass. If the superclass doesn't have a default constructor, this method is called recursively to add one if possible.

Returns:

constructor information

makeUniqueMethodName

public String makeUniqueMethodName(String name)

Make method name unique with generated suffix. The suffixed method name is tracked so that it will not be used again.

Parameters:

name - base name before suffix is appended

Returns:

name with unique suffix appended

deleteField

public boolean deleteField(String name)

Delete field from class.

Parameters:

name - field name

Returns:

true if field was present, false if not

deleteMethod

public boolean deleteMethod(String name,
                            String sig)

Delete method from class.

Parameters:

name - method name

sig - method signature

Returns:

true if method was present, false if not

getUseCount

public int getUseCount()

Get use count for class.

Returns:

use count for this class

incrementUseCount

public int incrementUseCount()

Increment use count for class.

Returns:

use count (after increment)

setUnmodifiable

public void setUnmodifiable()

Force class to unmodifiable state. This prevents any additions, changes, deletions to the file.

isModified

public boolean isModified()

Check if class has been modified.

Returns:

true if class is modified, false if not

setModified

public void setModified()

Set class modified flag.

isComplete

public boolean isComplete()

Check if class is in complete state.

Returns:

true if class is complete, false if not

computeHashCode

protected int computeHashCode()

Computes a hash code based on characteristics of the class. The characteristics used in computing the hash code include the base class, implemented interfaces, method names, field names, and package, but not the actual class name or signature. The current static version of the class is used for this computation, so if the class is being modified codeComplete() should be called before this method. Note that this is designed for use with the classes generated by JiBX, and is not necessarily a good model for general usage.

Returns:

computed hash code value

codeComplete

public void codeComplete()

Finalize current modified state of class. This converts the modified class state into a static form, then computes a hash code based on characteristics of the class. If the class has not been modified it just computes the hash code. Note that this won't initialize the array of superinterfaces if used with an interface, but that shouldn't be a problem since we don't create any interfaces.

hashCode

public int hashCode()

Get hash code. This is based on most characteristics of the class, including the actual methods, but excluding the class name. It is only valid after the codeComplete() method is called.

Overrides:

hashCode in class Object

Returns:

hash code based on code sequence

equalFieldOrMethods

public static boolean equalFieldOrMethods(org.apache.bcel.classfile.FieldOrMethod a,
                                          org.apache.bcel.classfile.FieldOrMethod b)

Compare two field or method items to see if they're equal. This handles only the comparisons that apply to both fields and methods. It does not include comparing access flags, since these may be different due to access requirements.

Parameters:

a - first field or method item

b - second field or method item

Returns:

true if the equal, false if not

equalMethods

public static boolean equalMethods(org.apache.bcel.classfile.Method a,
                                   org.apache.bcel.classfile.Method b)

Compare two methods to see if they're equal. This checks only the details of the exception handling and actual code, not the name or signature.

Parameters:

a - first method

b - second method

Returns:

true if the equal, false if not

equals

public boolean equals(Object obj)

Check if objects are equal. Compares first based on hash code, then on the actual contents of the class, including package, implemented interfaces, superclass, methods, and fields (but not the actual class name). It is only valid after the codeComplete() method is called.

Overrides:

equals in class Object

Parameters:

obj -

Returns:

true if equal objects, false if not

delete

public void delete()

Delete class file information. Deletes the class file for this class, if it exists. Does nothing if no class file has been generated.

writeFile

public void writeFile(OutputStream os)
               throws IOException

Write out modified class information. Writes the modified class file to an output stream.

Parameters:

os - output stream for writing modified class

Throws:

IOException - if error writing to file

writeFile

public void writeFile()
               throws IOException

Write out modified class information. Writes the modified class file back out to the original file. If the class file has not been modified, the original file is kept unchanged.

Throws:

IOException - if error writing to file

deriveClassName

public String deriveClassName(String prefix,
                              String suffix)

Derive generated class name. This generates a JiBX class name from the name of this class, using the supplied prefix and suffix information. The derived class name is always in the same package as this class.

Parameters:

prefix - generated class name prefix

suffix - generated class name suffix

Returns:

derived class name

setPaths

public static void setPaths(String[] paths)

Set class paths to be searched.

Parameters:

paths - ordered set of paths to be searched for class files

loadClass

public static Class loadClass(String name)

Try loading class from classpath.

Parameters:

name - fully qualified name of class to be loaded

Returns:

loaded class, or null if not found

getClassLoader

public static ClassLoader getClassLoader()

Get the classloader used for classes referenced in the binding.

Returns:

classloader