jist.runtime
Class Rewriter

java.lang.Object
  java.lang.ClassLoader
      jist.runtime.Rewriter

public final class Rewriter
extends java.lang.ClassLoader

A custom class loader used by the JIST system to modify standard Java applications at load-time to run under "Simulation Time". This implementation uses the Apache Byte-Code Engineering Library (BCEL).

Since:

JIST1.0

Version:

$Id: Rewriter.java,v 1.117 2005/03/13 16:11:54 barr Exp $

Author:

Rimon Barr <barr+jist@cs.cornell.edu>

Field Summary

private java.util.HashSet	blocking Methods that are blocking.
static java.lang.Class[]	blockingClass List of methods that are pre-defined to have every method blocking.
static java.lang.reflect.Member[]	blockingMethod List of methods that are pre-defined to be blocking.
static java.lang.String	CACHE_PREFIX Class cache prefix.
private java.lang.String	cacheDir Class disk-based cache directory.
private java.util.HashMap	calledBy Regular method call graph: (methodsig mapped to hashset(methodsig)).
private java.util.HashSet	continuable Methods should be rewritten to be Continuable.
static java.lang.reflect.Member[]	continuableMethod List of methods that are pre-defined to be continuable.
private static java.lang.String[]	ignoredPackages Class beginning with these strings are ignored, (used only when processedPackages is null).
static java.lang.String	JAVA_MAIN_NAME Name of the Java initialization method.
static java.lang.String	JIST_CONTINUATION_STATE_PREFIX Prefix for all classes to capture continuation state.
static java.lang.String	JIST_ENTITYREF Name of the entity self reference field.
static java.lang.String	JIST_FIELD_PREFIX Prefix of automatically generated fields.
static java.lang.String	JIST_METHOD_GET Prefix of generated field get accessor method.
static java.lang.String	JIST_METHOD_PREFIX Prefix of automatically generated methods.
static java.lang.String	JIST_METHOD_SET Prefix of generated field set accessor method.
static java.lang.String	JIST_METHODSTUB_PREFIX Prefix of generated method stub fields.
static java.lang.String	JIST_REF_SUFFIX Suffix of the entity self reference field.
static java.lang.String	JIST_STATIC_TRIGGER Name of the field used to trigger static initialization.
static java.lang.String	JIST_STATIC_TRIGGER_SUFFIX Suffix of the field used to trigger static intialization.
private org.apache.bcel.util.Repository	jistRepository (Possibly remote) Jist repository.
static org.apache.log4j.Logger	log Logger instance.
private java.util.HashMap	lookupCache Classpath lookup cache: (string to JavaClass).
static java.lang.reflect.Method	method_initializeMethodStubs Method stub of the generic static method initializer method.
private java.lang.String[]	processedPackages Classes beginning with these strings are processed and all others are ignored; or, if this variable is null, then ignore packages in ignoredPackages and process all others.
private static java.lang.Object	repositoryLock Mutex access to BCEL repository object.
private RemoteJist.ResourceFinderRemote	resources Resource locator (possibly remote).
private java.util.Vector	rewriters Installed rewrite traversal visitors.
private long	rewriterTime Time that the rewriter class was compiled.
private java.util.HashMap	rewritten Rewrite cache.
static java.lang.String[]	timeless List of objects that are pre-defined to be timeless.
private static java.util.Hashtable	timelessHash Hashtable containing the timeless list for rapid lookup.

Constructor Summary

Rewriter(java.lang.String[] processedPackages, java.lang.String cacheDir, RemoteJist.ResourceFinderRemote resources, java.io.PrintStream serverOut)
Initialize an Rewriter instance, with a list of packages to be processed (others are ignored).

Method Summary

boolean	addContinuable(java.lang.String sig) Add signature to list of continables.
static java.lang.String	classToFileName(java.lang.String classname) Convert class name into a filename.
void	clearLookupCache() Reset the JavaClass lookup cache.
void	computeContinuableFixedPoint() Compute continuable fixed-point using call-graph.
static boolean	containsMethod(org.apache.bcel.classfile.JavaClass jcl, java.lang.String methodname, org.apache.bcel.generic.Type methodreturn, org.apache.bcel.generic.Type[] methodargs) Return whether method contained (declared) within class.
java.lang.Class	define(org.apache.bcel.classfile.JavaClass jcl) Load a given BCEL class into the JVM.
protected java.lang.Class	findClass(java.lang.String name) Called by loadClass and actually does all the rewriting work, but checks in caches first.
java.lang.String[]	getAllClassReferences(java.lang.String classname) Return all the classes that are statically, directly referenced by this classes.
java.lang.String[]	getAllClassReferencesRecursively(java.lang.String classname) Return all the classes that are statically, recursively (directly and indirectly) referenced by this class.
static int	getConstantPoolSize(org.apache.bcel.classfile.JavaClass jcl) Return the (byte) size of the constant pool.
static java.lang.String	getContinutationClassName(org.apache.bcel.generic.MethodGen mg, int pc) Return the name of the class used to store the continuation of a method at a given "program counter" point.
java.lang.String	getDeclaringClass(java.lang.String classname, java.lang.String methodname, org.apache.bcel.generic.Type methodreturn, org.apache.bcel.generic.Type[] methodargs) Find class that declares a method, or null otherwise.
protected java.lang.Class	getDiskRewrittenClass(java.lang.String name) Read a cached rewritten class file from disk.
java.lang.String[]	getInterfaceNames(org.apache.bcel.classfile.JavaClass jcl) Return an array of the names of all interfaces implemented by a given class.
static java.lang.String	getMethodStubFieldName(java.lang.reflect.Method m) Return the name of the method stub field for a given method.
java.lang.String	getMethodStubFieldName(org.apache.bcel.generic.MethodGen mg) Return the name of the method stub field for a given method.
static java.lang.String	getMethodStubFieldName(java.lang.String methodName, java.lang.String sig) Return the name of the method stub field for a method with given name and signature (argument and return types).
static java.lang.String	getPrimitiveObjectConversionMethod(org.apache.bcel.generic.BasicType t) Return name of method used to convert a primitive type wrapper object to a primitive.
static java.lang.Class	getPrimitiveObjectType(org.apache.bcel.generic.BasicType t) Return a Class object for a given primitive Java Type.
org.apache.bcel.generic.Type	getRefType(org.apache.bcel.generic.Type t) Return the reference type of given type.
org.apache.bcel.generic.Type[]	getRefTypes(org.apache.bcel.generic.Type[] t) Return an array of reference types for a given array of types.
static java.lang.String	getSignature(java.lang.Class c) Return the internal Java signature string of a given class.
static java.lang.String	getSignature(java.lang.Class[] args, java.lang.Class ret) Return the internal Java signature string of a method.
static java.lang.String	getSignature(org.apache.bcel.generic.InvokeInstruction ii, org.apache.bcel.generic.ConstantPoolGen cpg) Return a method signature from an invocation instruction.
static java.lang.String	getSignature(java.lang.reflect.Member m) Return a method signature for given Java reflection method object.
static java.lang.String	getSignature(org.apache.bcel.generic.MethodGen mg) Return a method signature for given BCEL methodgen object.
static java.lang.String	getSignature(java.lang.String classname, java.lang.String methodname, org.apache.bcel.generic.Type methodreturn, org.apache.bcel.generic.Type[] methodargs) Return a method signature for the given information.
static org.apache.bcel.generic.Type	getType(java.lang.Class c) Return the BCEL Type object for a corresponding Java Class object.
static java.lang.String	getTypeClassname(org.apache.bcel.generic.Type t) Return the class name of the given Type or array type, or null for primitive types, or arrays of primitives.
static org.apache.bcel.generic.Type[]	getTypes(java.lang.Class[] c) Return a BCEL Type object array corresponding to Java Class object array.
static void	initializeMethodStubs(java.lang.String classname) Generic method for initializing method stubs of entities at runtime.
void	installPreRewriteTraversal(ClassTraversal.Visitor rewrite) Install a new rewrite traversal handler.
static boolean	isBlocking(org.apache.bcel.generic.MethodGen mg) Whether a given method has blocking semantics (whether the caller needs to call with continuation).
boolean	isBlocking(java.lang.String classname, java.lang.String methodname, org.apache.bcel.generic.Type methodreturn, org.apache.bcel.generic.Type[] methodargs) Whether a specified method has blocking semantics (whether the caller needs to call with continuation).
static boolean	isBlockingRuntime(java.lang.reflect.Method m) Whether a given regular entity method has blocking semantics (whether the caller needs to call with continuation).
static boolean	isBlockingRuntimeProxy(java.lang.reflect.Method m) Whether a given proxy entity method has blocking semantics (whether the caller needs to call with continuation).
boolean	isContinuable(org.apache.bcel.generic.InvokeInstruction ii, org.apache.bcel.generic.ConstantPoolGen cpg) Whether a given invocation target is "continuable".
boolean	isContinuable(org.apache.bcel.generic.MethodGen mg) Whether a given method is marked as "continuable".
boolean	isDoNotRewrite(org.apache.bcel.classfile.JavaClass c) Determine whether given class should not be rewritten.
boolean	isEntity(org.apache.bcel.classfile.JavaClass c) Determine whether given class is an entity.
boolean	isEntity(java.lang.String name) Determine whether given class is an entity.
static boolean	isEntityRuntime(java.lang.Class c) Determine whether given class is an entity.
boolean	isIgnored(java.lang.String classname) Determine whether a class should be rewritten or left alone.
static boolean	isIgnoredStatic(java.lang.String classname) Determine whether a class should be rewritten or left alone.
boolean	isProxiable(org.apache.bcel.classfile.JavaClass c) Determine whether given class is an entity.
boolean	isProxiable(java.lang.String name) Determine whether given class is proxiable.
boolean	isRefType(org.apache.bcel.generic.Type t) Return whether this type is a non-entity.
boolean	isRefTypes(org.apache.bcel.generic.Type[] t) Return whether all types in array are non-entities.
boolean	isTimeless(org.apache.bcel.classfile.JavaClass c) Determine whether given class is timeless.
boolean	isTimeless(java.lang.String name) Determine whether given class is timeless.
boolean	isTimeless(org.apache.bcel.generic.Type type) Determine whether given type is timeclass.
static boolean	isTimelessRuntime(java.lang.Class c) Determine whether given class is timeless.
java.lang.Class	loadClass(java.lang.String name, boolean resolve) Find and load class.
static void	logAccessFlags(org.apache.bcel.classfile.AccessFlags a) Emit the access flags to Rewriter log.
org.apache.bcel.classfile.JavaClass	lookupJavaClass(java.lang.String name) Search the class path and return requested BCEL JavaClass object.
int	prime(java.lang.String classname) Prime the rewriter doing a breadth-first search loading (and rewrite) of all classes transitively statically referenced.
protected void	putDiskRewrittenClass(java.lang.String name, byte[] b) Write a rewritten class file to the disk cache.
protected org.apache.bcel.classfile.JavaClass	rewriteClass(org.apache.bcel.classfile.JavaClass jcl) Performs JiST rewriting of given JavaClass file.
static void	setClassName(org.apache.bcel.classfile.JavaClass jcl, java.lang.String name) Modify the name of a class.
void	updateCallGraphAndContinuable(org.apache.bcel.classfile.JavaClass jcl) Update call-graph with methods of a new class.

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findLibrary, findLoadedClass, findResource, findResources, findSystemClass, getPackage, getPackages, getParent, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

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

Field Detail

JAVA_MAIN_NAME

public static final java.lang.String JAVA_MAIN_NAME

Name of the Java initialization method.

See Also:

Constant Field Values

JIST_METHOD_PREFIX

public static final java.lang.String JIST_METHOD_PREFIX

Prefix of automatically generated methods.

See Also:

Constant Field Values

JIST_FIELD_PREFIX

public static final java.lang.String JIST_FIELD_PREFIX

Prefix of automatically generated fields.

See Also:

Constant Field Values

JIST_METHODSTUB_PREFIX

public static final java.lang.String JIST_METHODSTUB_PREFIX

Prefix of generated method stub fields.

See Also:

Constant Field Values

JIST_METHOD_SET

public static final java.lang.String JIST_METHOD_SET

Prefix of generated field set accessor method.

See Also:

Constant Field Values

JIST_METHOD_GET

public static final java.lang.String JIST_METHOD_GET

Prefix of generated field get accessor method.

See Also:

Constant Field Values

JIST_REF_SUFFIX

public static final java.lang.String JIST_REF_SUFFIX

Suffix of the entity self reference field.

See Also:

Constant Field Values

JIST_ENTITYREF

public static final java.lang.String JIST_ENTITYREF

Name of the entity self reference field.

See Also:

Constant Field Values

JIST_STATIC_TRIGGER_SUFFIX

public static final java.lang.String JIST_STATIC_TRIGGER_SUFFIX

Suffix of the field used to trigger static intialization.

See Also:

Constant Field Values

JIST_STATIC_TRIGGER

public static final java.lang.String JIST_STATIC_TRIGGER

Name of the field used to trigger static initialization.

See Also:

Constant Field Values

JIST_CONTINUATION_STATE_PREFIX

public static final java.lang.String JIST_CONTINUATION_STATE_PREFIX

Prefix for all classes to capture continuation state.

See Also:

Constant Field Values

log

public static final org.apache.log4j.Logger log

Logger instance.

CACHE_PREFIX

public static final java.lang.String CACHE_PREFIX

Class cache prefix.

See Also:

Constant Field Values

timeless

public static final java.lang.String[] timeless

List of objects that are pre-defined to be timeless.

timelessHash

private static java.util.Hashtable timelessHash

Hashtable containing the timeless list for rapid lookup.

blockingMethod

public static java.lang.reflect.Member[] blockingMethod

List of methods that are pre-defined to be blocking.

continuableMethod

public static java.lang.reflect.Member[] continuableMethod

List of methods that are pre-defined to be continuable.

blockingClass

public static final java.lang.Class[] blockingClass

List of methods that are pre-defined to have every method blocking.

ignoredPackages

private static final java.lang.String[] ignoredPackages

Class beginning with these strings are ignored, (used only when processedPackages is null).

repositoryLock

private static java.lang.Object repositoryLock

Mutex access to BCEL repository object.

processedPackages

private java.lang.String[] processedPackages

Classes beginning with these strings are processed and all others are ignored; or, if this variable is null, then ignore packages in ignoredPackages and process all others.

rewritten

private java.util.HashMap rewritten

Rewrite cache. This is not just for performance... Must have for type-safety.

cacheDir

private java.lang.String cacheDir

Class disk-based cache directory.

resources

private RemoteJist.ResourceFinderRemote resources

Resource locator (possibly remote).

jistRepository

private org.apache.bcel.util.Repository jistRepository

(Possibly remote) Jist repository.

rewriterTime

private long rewriterTime

Time that the rewriter class was compiled.

continuable

private java.util.HashSet continuable

Methods should be rewritten to be Continuable.

blocking

private java.util.HashSet blocking

Methods that are blocking.

rewriters

private java.util.Vector rewriters

Installed rewrite traversal visitors.

lookupCache

private java.util.HashMap lookupCache

Classpath lookup cache: (string to JavaClass).

calledBy

private java.util.HashMap calledBy

Regular method call graph: (methodsig mapped to hashset(methodsig)).

method_initializeMethodStubs

public static java.lang.reflect.Method method_initializeMethodStubs

Method stub of the generic static method initializer method.

Constructor Detail

Rewriter

public Rewriter(java.lang.String[] processedPackages,
                java.lang.String cacheDir,
                RemoteJist.ResourceFinderRemote resources,
                java.io.PrintStream serverOut)

Initialize an Rewriter instance, with a list of packages to be processed (others are ignored).

Parameters:

processedPackages - list of packages to process, or null to process all packages, except those in the (default) ignoredPackages list.

cacheDir - directory for rewritten classfile cache

resources - remote resources finder

serverOut - server machine output stream

Method Detail

loadClass

public java.lang.Class loadClass(java.lang.String name,
                                 boolean resolve)
                          throws java.lang.ClassNotFoundException,
                                 java.lang.VerifyError

Find and load class. This method is invoked by the VM.

Overrides:

loadClass in class java.lang.ClassLoader

Parameters:

name - qualified class name (e.g. java.lang.String)

resolve - not relevant

Returns:

requested class object

Throws:

java.lang.ClassNotFoundException - thrown if class can not be found

java.lang.VerifyError - throw if given class does not satify various JIST programming constraints.

findClass

protected java.lang.Class findClass(java.lang.String name)
                             throws java.lang.ClassNotFoundException,
                                    java.lang.VerifyError

Called by loadClass and actually does all the rewriting work, but checks in caches first.

Overrides:

findClass in class java.lang.ClassLoader

Parameters:

name - qualified class name (e.g. java.lang.String)

Returns:

requested class object

Throws:

java.lang.ClassNotFoundException - thrown if class can not be found

java.lang.VerifyError - throw if given class does not satify various JIST programming constraints.

lookupJavaClass

public org.apache.bcel.classfile.JavaClass lookupJavaClass(java.lang.String name)
                                                    throws java.lang.ClassNotFoundException

Search the class path and return requested BCEL JavaClass object. This is the ONLY point through which the Rewriter retrieves new JavaClass objects. Therefore, it is also a convenient point to perform caching and incremental maintenance of the call-graph.

Parameters:

name - classname

Returns:

BCEL JavaClass object

Throws:

java.lang.ClassNotFoundException - when class not found

clearLookupCache

public void clearLookupCache()

Reset the JavaClass lookup cache.

define

public java.lang.Class define(org.apache.bcel.classfile.JavaClass jcl)

Load a given BCEL class into the JVM.

Parameters:

jcl - BCEL Java class

Returns:

loaded class object

rewriteClass

protected org.apache.bcel.classfile.JavaClass rewriteClass(org.apache.bcel.classfile.JavaClass jcl)
                                                    throws java.lang.ClassNotFoundException,
                                                           java.lang.VerifyError

Performs JiST rewriting of given JavaClass file.

Parameters:

jcl - BCEL JavaClass structure to rewrite

Returns:

rewritten class object

Throws:

java.lang.VerifyError - throw if given class does not satify various JIST programming constraints.

java.lang.ClassNotFoundException - failure to find referenced class

getDiskRewrittenClass

protected java.lang.Class getDiskRewrittenClass(java.lang.String name)

Read a cached rewritten class file from disk.

Parameters:

name - class name

Returns:

rewritten class, or null if it does not exist/invalid

putDiskRewrittenClass

protected void putDiskRewrittenClass(java.lang.String name,
                                     byte[] b)

Write a rewritten class file to the disk cache.

Parameters:

name - class name

b - class bytecode

addContinuable

public boolean addContinuable(java.lang.String sig)
                       throws java.lang.VerifyError

Add signature to list of continables. Verify that it is not a constructor, and return whether it is newly discovered.

Parameters:

sig - continuable to add

Returns:

whether this is a newly found continuable method

Throws:

java.lang.VerifyError - if signature is of an initialization method

updateCallGraphAndContinuable

public void updateCallGraphAndContinuable(org.apache.bcel.classfile.JavaClass jcl)
                                   throws java.lang.ClassNotFoundException

Update call-graph with methods of a new class.

Parameters:

jcl - BCEL class object to analyze

Throws:

java.lang.ClassNotFoundException - failure to load class in call graph

computeContinuableFixedPoint

public void computeContinuableFixedPoint()

Compute continuable fixed-point using call-graph.

getAllClassReferences

public java.lang.String[] getAllClassReferences(java.lang.String classname)
                                         throws java.lang.ClassNotFoundException

Return all the classes that are statically, directly referenced by this classes.

Parameters:

classname - name of class to inspect

Returns:

array of classes statically referenced directly

Throws:

java.lang.ClassNotFoundException - failure to find referenced class

getAllClassReferencesRecursively

public java.lang.String[] getAllClassReferencesRecursively(java.lang.String classname)
                                                    throws java.lang.ClassNotFoundException

Return all the classes that are statically, recursively (directly and indirectly) referenced by this class.

Parameters:

classname - name of class to inspect

Returns:

array of classes statically referenced directly or indirectly

Throws:

java.lang.ClassNotFoundException - failure to find referenced class

getInterfaceNames

public java.lang.String[] getInterfaceNames(org.apache.bcel.classfile.JavaClass jcl)
                                     throws java.lang.ClassNotFoundException

Return an array of the names of all interfaces implemented by a given class.

Parameters:

jcl - BCEL JavaClass object to inspect

Returns:

array of the names of all interfaces implemented.

Throws:

java.lang.ClassNotFoundException - interface classes not found

getDeclaringClass

public java.lang.String getDeclaringClass(java.lang.String classname,
                                          java.lang.String methodname,
                                          org.apache.bcel.generic.Type methodreturn,
                                          org.apache.bcel.generic.Type[] methodargs)
                                   throws java.lang.ClassNotFoundException

Find class that declares a method, or null otherwise.

Parameters:

classname - classname to initiate search from

methodname - name of method being sought

methodreturn - BCEL return type of method being sought

methodargs - BCEL argument type of method being sought

Returns:

name of class that declares given method

Throws:

java.lang.ClassNotFoundException - parent class not found

containsMethod

public static boolean containsMethod(org.apache.bcel.classfile.JavaClass jcl,
                                     java.lang.String methodname,
                                     org.apache.bcel.generic.Type methodreturn,
                                     org.apache.bcel.generic.Type[] methodargs)

Return whether method contained (declared) within class.

Parameters:

jcl - BCEL JavaClass object to inspect

methodname - method name

methodreturn - method return BCEL type

methodargs - method parameter BCEL types

Returns:

whether method is contained within class

isIgnored

public boolean isIgnored(java.lang.String classname)

Determine whether a class should be rewritten or left alone. If processedPackages is defined, then we only process packages with those prefixes. Otherwise, any package that does not begin with a prefix in the ignoredPackages array is rewritten.

Parameters:

classname - given class name

Returns:

whether the given class should be rewritten

isIgnoredStatic

public static boolean isIgnoredStatic(java.lang.String classname)

Determine whether a class should be rewritten or left alone. Any package that does not begin with a prefix in the ignoredPackages array is rewritten.

Parameters:

classname - given class name

Returns:

whether the given class should be rewritten

isEntity

public boolean isEntity(org.apache.bcel.classfile.JavaClass c)
                 throws java.lang.ClassNotFoundException

Determine whether given class is an entity. A class is an entity if and only if it implements the JistAPI.Entity interface.

Parameters:

c - BCEL class object

Returns:

whether given class is an entity

Throws:

java.lang.ClassNotFoundException

See Also:

JistAPI.Entity

isEntity

public boolean isEntity(java.lang.String name)
                 throws java.lang.ClassNotFoundException

Determine whether given class is an entity. A class is an entity if and only if it implements the JistAPI.Entity interface.

Parameters:

name - class name

Returns:

whether given class is an entity

Throws:

java.lang.ClassNotFoundException - class could not be loaded

See Also:

JistAPI.Entity

isEntityRuntime

public static boolean isEntityRuntime(java.lang.Class c)

Determine whether given class is an entity. A class is an entity (at runtime) if and only if it implement the Entity interface.

Parameters:

c - runtime class object

Returns:

whether given class is an entity

See Also:

JistAPI.Entity

isTimeless

public boolean isTimeless(org.apache.bcel.classfile.JavaClass c)
                   throws java.lang.ClassNotFoundException

Determine whether given class is timeless. A class is timeless if and only if it implements the JistAPI.Timeless interface, or the object is immutable, as determined automatically or through membership in the static timeless list.

Parameters:

c - BCEL class object

Returns:

whether given class is an timeless

Throws:

java.lang.ClassNotFoundException

See Also:

JistAPI.Timeless

isTimeless

public boolean isTimeless(java.lang.String name)
                   throws java.lang.ClassNotFoundException

Determine whether given class is timeless. A class is timeless if and only if it implements the JistAPI.Timeless interface, or it is determined to be immutable.

Parameters:

name - class name

Returns:

whether given class is an entity

Throws:

java.lang.ClassNotFoundException

See Also:

JistAPI.Entity

isTimeless

public boolean isTimeless(org.apache.bcel.generic.Type type)
                   throws java.lang.ClassNotFoundException

Determine whether given type is timeclass. A type is timeless if and only if it is a primitive type or it is a timeless class

Parameters:

type - type

Returns:

whether t is a timeless

Throws:

java.lang.ClassNotFoundException

isTimelessRuntime

public static boolean isTimelessRuntime(java.lang.Class c)

Determine whether given class is timeless. A class is timeless (at runtime) if and only if it implements the Timeless interface.

Parameters:

c - runtime class object

Returns:

whether given class is an timeless

See Also:

JistAPI.Timeless

isProxiable

public boolean isProxiable(org.apache.bcel.classfile.JavaClass c)
                    throws java.lang.ClassNotFoundException

Determine whether given class is an entity. A class is an entity if and only if it implements the JistAPI.Entity interface.

Parameters:

c - BCEL class object

Returns:

whether given class is an entity

Throws:

java.lang.ClassNotFoundException

See Also:

JistAPI.Entity

isProxiable

public boolean isProxiable(java.lang.String name)
                    throws java.lang.ClassNotFoundException

Determine whether given class is proxiable. A class is proxiable if and only if it implements the JistAPI.Proxiable interface.

Parameters:

name - class name

Returns:

whether given class is an entity

Throws:

java.lang.ClassNotFoundException - class could not be loaded

See Also:

JistAPI.Entity

isBlocking

public static boolean isBlocking(org.apache.bcel.generic.MethodGen mg)

Whether a given method has blocking semantics (whether the caller needs to call with continuation). A method is blocking iff it declares that it throws a JistAPI.Continuation.

Parameters:

mg - method object

Returns:

whether method is blocking

isBlocking

public boolean isBlocking(java.lang.String classname,
                          java.lang.String methodname,
                          org.apache.bcel.generic.Type methodreturn,
                          org.apache.bcel.generic.Type[] methodargs)
                   throws java.lang.ClassNotFoundException

Whether a specified method has blocking semantics (whether the caller needs to call with continuation). A method is blocking iff it declares that it throws a JistAPI.Continuation.

Parameters:

classname - class name

methodname - method name

methodreturn - method return type

methodargs - method parameter types

Returns:

whether method is blocking

Throws:

java.lang.ClassNotFoundException - could not find parent classes

isBlockingRuntime

public static boolean isBlockingRuntime(java.lang.reflect.Method m)

Whether a given regular entity method has blocking semantics (whether the caller needs to call with continuation). A regular (non-proxy) entity method is blocking, at runtime, iff it declares that it throws a Event.ContinuationFrame.

Parameters:

m - method object

Returns:

whether regular entity method is blocking

isBlockingRuntimeProxy

public static boolean isBlockingRuntimeProxy(java.lang.reflect.Method m)

Whether a given proxy entity method has blocking semantics (whether the caller needs to call with continuation). A proxy entity method is blocking, at runtime, iff it declares that it throws a JistAPI.Continuation.

Parameters:

m - method object

Returns:

whether proxy entity method is blocking

isContinuable

public boolean isContinuable(org.apache.bcel.generic.MethodGen mg)

Whether a given method is marked as "continuable". Continuable methods are methods that calls blocking methods (those that declare throws Continuation) or other continuable methods in the same entity.

Parameters:

mg - BCEL MethodGen object

Returns:

whether method is "continuable"

isContinuable

public boolean isContinuable(org.apache.bcel.generic.InvokeInstruction ii,
                             org.apache.bcel.generic.ConstantPoolGen cpg)

Whether a given invocation target is "continuable". Continuable methods are methods that calls blocking methods (those that declare throws Continuation) or other continuable methods in the same entity.

Parameters:

ii - invocation instruction

cpg - class constant pool

Returns:

whether invocation target is "continuable"

isDoNotRewrite

public boolean isDoNotRewrite(org.apache.bcel.classfile.JavaClass c)
                       throws java.lang.ClassNotFoundException

Determine whether given class should not be rewritten. A class can turn off the rewriter by implementing the JistAPI.DoNotRewrite interface.

Parameters:

c - BCEL class object

Returns:

whether given class has rewriting disabled

Throws:

java.lang.ClassNotFoundException

See Also:

JistAPI.DoNotRewrite

setClassName

public static void setClassName(org.apache.bcel.classfile.JavaClass jcl,
                                java.lang.String name)

Modify the name of a class.

Parameters:

jcl - BCEL class object

name - new name for class

logAccessFlags

public static void logAccessFlags(org.apache.bcel.classfile.AccessFlags a)

Emit the access flags to Rewriter log.

Parameters:

a - access flags to log

getRefType

public org.apache.bcel.generic.Type getRefType(org.apache.bcel.generic.Type t)
                                        throws java.lang.ClassNotFoundException

Return the reference type of given type. The reference type of an object type is an EntityRef if the object is an entity. All other types (non-entity objects, arrays and primitives) are their own reference types. Array types are processed recursively.

Parameters:

t - Java type

Returns:

reference type of given type

Throws:

java.lang.ClassNotFoundException

See Also:

EntityRef

getRefTypes

public org.apache.bcel.generic.Type[] getRefTypes(org.apache.bcel.generic.Type[] t)
                                           throws java.lang.ClassNotFoundException

Return an array of reference types for a given array of types. The reference type of an object type is an EntityRef if the object is an entity. All other types (non-entity objects, arrays and primitives) are their own reference types. Array types are processed recursively.

Parameters:

t - array of Java types

Returns:

array of reference type of given array

Throws:

java.lang.ClassNotFoundException

isRefType

public boolean isRefType(org.apache.bcel.generic.Type t)
                  throws java.lang.ClassNotFoundException

Return whether this type is a non-entity. (i.e. whether it needs to be converted into an entity reference)

Parameters:

t - type

Returns:

whether t is a non-entity

Throws:

java.lang.ClassNotFoundException

isRefTypes

public boolean isRefTypes(org.apache.bcel.generic.Type[] t)
                   throws java.lang.ClassNotFoundException

Return whether all types in array are non-entities. (i.e. whether anything in the array needs to be converted to an entity reference)

Parameters:

t - array of types

Returns:

whether all types in t are non-entities

Throws:

java.lang.ClassNotFoundException

getType

public static org.apache.bcel.generic.Type getType(java.lang.Class c)

Return the BCEL Type object for a corresponding Java Class object.

Parameters:

c - type given as Java class object

Returns:

given type as a BCEL Type object

getTypes

public static org.apache.bcel.generic.Type[] getTypes(java.lang.Class[] c)

Return a BCEL Type object array corresponding to Java Class object array.

Parameters:

c - type array given as Java class objects

Returns:

given type array converted to BCEL Type objects

getPrimitiveObjectType

public static java.lang.Class getPrimitiveObjectType(org.apache.bcel.generic.BasicType t)

Return a Class object for a given primitive Java Type.

Parameters:

t - primitive type given as BCEL Type object

Returns:

primitive type as Java class object

getPrimitiveObjectConversionMethod

public static java.lang.String getPrimitiveObjectConversionMethod(org.apache.bcel.generic.BasicType t)

Return name of method used to convert a primitive type wrapper object to a primitive. (eg. doubleValue to convert Double to double.)

Parameters:

t - primitive BCEL type object

Returns:

name of method used to convert a primitive type wrapper object to a primitive type.

getSignature

public static java.lang.String getSignature(java.lang.Class c)

Return the internal Java signature string of a given class.

Parameters:

c - given class type to convert

Returns:

internal Java signature of given class type

getSignature

public static java.lang.String getSignature(java.lang.Class[] args,
                                            java.lang.Class ret)

Return the internal Java signature string of a method.

Parameters:

args - method argument types

ret - method return type

Returns:

internal Java signature of method with given parameter and return types

getSignature

public static java.lang.String getSignature(org.apache.bcel.generic.MethodGen mg)

Return a method signature for given BCEL methodgen object.

Parameters:

mg - BCEL MethodGen object

Returns:

Java method signature

getSignature

public static java.lang.String getSignature(org.apache.bcel.generic.InvokeInstruction ii,
                                            org.apache.bcel.generic.ConstantPoolGen cpg)

Return a method signature from an invocation instruction.

Parameters:

ii - invocation instruction

cpg - class constant pool

Returns:

method signature

getSignature

public static java.lang.String getSignature(java.lang.reflect.Member m)

Return a method signature for given Java reflection method object.

Parameters:

m - Java reflection method object

Returns:

Java method signature

getSignature

public static java.lang.String getSignature(java.lang.String classname,
                                            java.lang.String methodname,
                                            org.apache.bcel.generic.Type methodreturn,
                                            org.apache.bcel.generic.Type[] methodargs)

Return a method signature for the given information.

Parameters:

classname - class name

methodname - method name

methodreturn - method return BCEL type

methodargs - method argument BCEL types

Returns:

method signature string

getMethodStubFieldName

public java.lang.String getMethodStubFieldName(org.apache.bcel.generic.MethodGen mg)
                                        throws java.lang.ClassNotFoundException

Return the name of the method stub field for a given method.

Parameters:

mg - BCEL method generator object

Returns:

name of method stub field for given method

Throws:

java.lang.ClassNotFoundException

getMethodStubFieldName

public static java.lang.String getMethodStubFieldName(java.lang.reflect.Method m)

Return the name of the method stub field for a given method.

Parameters:

m - Java method object

Returns:

name of method stub field for given method

getMethodStubFieldName

public static java.lang.String getMethodStubFieldName(java.lang.String methodName,
                                                      java.lang.String sig)

Return the name of the method stub field for a method with given name and signature (argument and return types).

Parameters:

methodName - name of method

sig - method signature (internal Java representation of method arguments and return types)

Returns:

name of method stub field for method with given name and signature

getContinutationClassName

public static java.lang.String getContinutationClassName(org.apache.bcel.generic.MethodGen mg,
                                                         int pc)

Return the name of the class used to store the continuation of a method at a given "program counter" point. The name needs to be a valid class name, to be in the same package as the method's class, to be unique among other (class, method name, method arguments, pc) values.

Parameters:

mg - method being continued

pc - "program counter" point within method

Returns:

name of class used to store continuation state

getTypeClassname

public static java.lang.String getTypeClassname(org.apache.bcel.generic.Type t)

Return the class name of the given Type or array type, or null for primitive types, or arrays of primitives.

Parameters:

t - BCEL Type object

Returns:

class name of type, or null for primitives

getConstantPoolSize

public static int getConstantPoolSize(org.apache.bcel.classfile.JavaClass jcl)

Return the (byte) size of the constant pool.

Parameters:

jcl - BCEL Java class object

Returns:

size of constant pool in bytes

initializeMethodStubs

public static void initializeMethodStubs(java.lang.String classname)

Generic method for initializing method stubs of entities at runtime. This method uses reflection to simply initialize the static stubs in a generic manner at load time with Method objects. It is called by each entity in its class initializer. The same (or more specific) code could have been placed in each class initializer, but this saves a lot of bytecode generation during transformation, and has no performance implications.

Parameters:

classname - class name that should have its static stubs initialized with Method objects

prime

public int prime(java.lang.String classname)
          throws java.lang.ClassNotFoundException

Prime the rewriter doing a breadth-first search loading (and rewrite) of all classes transitively statically referenced.

Parameters:

classname - root class of the breadth-first traversal

Returns:

number of classes loaded

Throws:

java.lang.ClassNotFoundException - when requested or (directly or indirectly) referenced classes cannot be loaded

installPreRewriteTraversal

public void installPreRewriteTraversal(ClassTraversal.Visitor rewrite)

Install a new rewrite traversal handler.

Parameters:

rewrite - rewriter traversal handler

classToFileName

public static java.lang.String classToFileName(java.lang.String classname)

Convert class name into a filename.

Parameters:

classname - class name to converted

Returns:

file name containing given class