JRE Emulation Reference

J2ObjC includes a library that emulates a subset of the Java runtime library (lib/libjre_emul.a). The list below shows the set of JRE packages, types and methods that J2ObjC can translate automatically. Note that in some cases, only a subset of methods is supported for a given type; if so, the supported methods are listed below the class name.

NOTE: the JRE emulation support is rapidly evolving, so this page may lag behind the actual release contents. To find the exact list of classes and methods, check the J2ObjC distribution's include directory. Each supported class will have a matching header (.h) file, which lists all supported methods.

• java.beans
• java.io
• java.lang
• java.lang.annotation
• java.lang.ref
• java.lang.reflect
• java.math
• java.nio
• java.nio.charset
• java.text
• java.util
• java.util.concurrent
• java.util.concurrent.atomic
• java.util.concurrent.locks
• java.util.regex
• javax.xml
• javax.xml.parsers
• javax.xml.transform
• org.w3c.dom
• org.w3c.dom.ls
• org.xml.sax
• org.xml.sax.ext
• org.xml.sax.helpers

java.beans

IndexedPropertyChangeEvent	PropertyChangeEvent	PropertyChangeListener	PropertyChangeListenerProxy
PropertyChangeSupport

java.io

BufferedInputStream	BufferedOutputStream	BufferedReader	BufferedWriter
ByteArrayInputStream	ByteArrayOutputStream	CharArrayReader	CharArrayWriter
CharConversionException	Closeable	DataInput	DataInputStream
DataOutput	DataOutputStream	EOFException	Externalizable
File	FileDescriptor	FileFilter	FileInputStream
FileNotFoundException	FileOutputStream	FileReader	FileWriter
FilenameFilter	FilterInputStream	FilterOutputStream	FilterReader
FilterWriter	Flushable	IOException	InputStream
InputStreamReader	InterruptedIOException	InvalidClassException	InvalidObjectException
LineNumberReader	NotActiveException	NotSerializeableException	ObjectInput
ObjectInputStream	ObjectInputValidation	ObjectOutput	ObjectOutputStream
ObjectStreamClass	ObjectStreamConstants	ObjectStreamException	ObjectStreamField
OptionalDataException	OutputStream	OutputStreamWriter	PipedInputStream
PipedOutputStream	PipedReader	PipedWriter	PrintStream
PrintWriter	PushbackInputStream	PushbackReader	RandomAccessFile
Reader	SequenceInputStream	Serializable	SerializablePermission
StreamCorruptedException	StreamTokenizer	StringReader	StringWriter
SyncFailedException	UTFDataFormatException	UnsupportedEncodingException	WriteAbortedException
Writer

java.lang

Void

AbstractMethodError	Appendable	ArithmeticException	ArrayIndexOutOfBoundsException
ArrayStoreException	AssertionError	AutoCloseable	Boolean
Byte	CharSequence	Character	Class
ClassCastException	ClassFormatError	ClassLoader	ClassNotFoundException
CloneNotSupportedException	Comparable	Deprecated	Double
Enum	Error	Exception	ExceptionInInitializerError
Float	IllegalAccessException	IllegalArgumentException	IllegalMonitorState
IllegalStateException	IllegalThreadStateException	IncompatibleClassChangeError	IndexOutOfBoundsException
InstantiationException	Integer	InternalError	InterruptedException
Iterable	LinkageError	Long	Math
NegativeArraySizeException	NoSuchFieldError	NoSuchFieldException	NoSuchMethodError
NoSuchMethodException	NullPointerException	Number	NumberFormatException
Object	Override	Package	Readable
Runnable	RuntimeException	SafeArgs	SecurityException
SecurityManager	Short	StackTraceElement	StrictMath
String	StringBuffer	StringBuilder	StringIndexOutOfBoundsException
SuppressWarnings	System	Thread	ThreadDeath
ThreadGroup	ThreadLocal	Throwable	TypeNotPresentException
UnsupportedOperationException	VirtualMachineError

• System:
• Supported methods: currentTimeMillis(), identityHashCode(), arrancopy(), nanoTime(), exit()
• System properties: only os.name, file.separator, line.separator, path.separator (plus any defined using System.setProperty())
• Object, Number, and String are supported but do not have header (.h) files, because these classes are translated directly to their respective Foundation classes (NSObject, NSNumber, and NSString). Class is supported by J2ObjC's IOSClass.

java.lang.annotation

Annotation	AnnotationFormatError	AnnotationTypeMismatchException	Documented
ElementType	IncompleteAnnotationException	Inherited	Retention
RetentionPolicy	Target

java.lang.ref

PhantomReference	Reference	ReferenceQueue	SoftReference
WeakReference

java.lang.reflect

AccessibleObject	AnnotatedElement	Array	Constructor
ExecutableMember	Field	GenericArrayType	GenericDeclaration
GenericSignatureFormatError	InvocationHandler	InvocationTargetException	MalformedParameterizedTypeException
Member	Method	Modifier	ParameterizedType
Proxy	ReflectPermission	Type	TypeVariable
UndeclaredThrowableException	WildcardType

java.math

BigDecimal	BigInteger	BitLevel	Conversion
Division	Elementary	Logical	MathContext
Multiplication	Primality	RoundingMode

java.nio

Buffer	BufferFactory	BufferOverflowException	BufferUnderflowException
ByteBuffer	ByteOrder	CharArrayBuffer	CharBuffer
CharSequenceAdapter	DoubleArrayBuffer	DoubleBuffer	FloatArrayBuffer
FloatBuffer	HeapByteBuffer	IntArrayBuffer	IntBuffer
InvalidMarkException	LongArrayBuffer	LongBuffer	ReadOnlyBufferException
ReadOnlyCharArrayBuffer	ReadOnlyDoubleArrayBuffer	ReadOnlyFloatArrayBuffer	ReadOnlyHeapByteBuffer
ReadOnlyIntArrayBuffer	ReadOnlyLongArrayBuffer	ReadOnlyShortArrayBuffer	ReadWriteCharArrayBuffer
ReadWriteDoubleArrayBuffer	ReadWriteFloatArrayBuffer	ReadWriteHeapByteBuffer	ReadWriteIntArrayBuffer
ReadWriteLongArrayBuffer	ReadWriteShortArrayBuffer	ShortArrayBuffer	ShortBuffer

java.nio.charset

CharsetCodingException	Charset	CharsetDecoder	CharsetEncoder
Charsets	CoderMalfunctionError	CoderResult	CodingErrorAction
IllegalCharsetNameException	MalformedInputException	StandardCharsets	UnmappableCharacterException
UnsupportedCharsetException

java.text

Annotation	AttributedCharacterIterator	AttributedString	CharacterIterator
ChoiceFormat	CollationKey	Collator	DateFormat
DateFormatSymbols	DecimalFormat	DecimalFormatSymbols	FieldPosition
Format	MessageFormat	NumberFormat	ParseException
ParsePosition	SimpleDateFormat

java.util

AbstractCollection	AbstractList	AbstractMap	AbstractQueue
AbstractSequentialList	AbstractSet	ArrayDeque	ArrayList
Arrays	BitSet	Calendar	Collection
Collections	Comparator	ConcurrentModificationException	Currency
Date	Deque	Dictionary	DuplicateFormatFlagsException
EventListener	EmptyStackException	EnumMap	EnumSet
Enumeration	EventListener	EventListenerProxy	EventObject
GregorianCalendar	HashMap	HashSet	Hashtable
IdentityHashMap	IllegalFormatCodePointException	IllegalFormatConversionException	IllegalFormatException
IllegalFormatFlagsException	IllegalFormatPrecisionException	IllegalFormatWidthException	InputMismatchException
InputMismatchException	InvalidPropertiesFormatException	Iterator	LinkedHashMap
LinkedHashSet	LinkedList	List	ListIterator
ListResourceBundle	Locale	Map	MissingFormatArgumentException
MissingFormatWidthException	MissingResourceException	NavigableMap	NavigableSet
NoSuchElementException	Observable	Observer	PriorityQueue
Properties	PropertyResourceBundle	Queue	Random
RandomAccess	ResourceBundle	ServiceConfigurationError	ServiceLoader
Set	SimpleTimeZone	SortedMap	SortedSet
Stack	TimeZone	Timer	TimerTask
TreeMap	TreeSet	UUID	UnknownFormatConversionException
UnknownFormatFlagsException	Vector	WeakHashMap

java.util.concurrent

AbstractExecutorService	ArrayBlockingQueue	BlockingDeque	BlockingQueue
BrokenBarrierException	Callable	CancellationException	CompletionService
ConcurrentHashMap	ConcurrentLinkedDeque	ConcurrentLinkedQueue	ConcurrentMap
ConcurrentNavigableMap	ConcurrentSkipListMap	ConcurrentSkipListSet	CopyOnWriteArrayList
CopyOnWriteArraySet	CountDownLatch	CyclicBarrier	DelayQueue
Delayed	Exchanger	ExecutionException	Executor
ExecutorCompletionService	ExecutorService	Executors	ForkJoinPool
ForkJoinTask	ForkJoinWorkerThread	Future	FutureTask
LinkedBlockingDeque	LinkedBlockingQueue	LinkedTransferQueue	Phaser
PriorityBlockingQueue	RecursiveAction	RecursiveTask	RejectedExecutionException
RejectedExecutionHandler	RunnableFuture	RunnableScheduledFuture	ScheduledExecutorService
ScheduledFuture	ScheduledThreadPoolExecutor	Semaphore	SynchronousQueue
ThreadFactory	ThreadLocalRandom	ThreadPoolExecutor	TimeUnit
TimeoutException	TransferQueue

java.util.concurrent.atomic

AtomicBoolean	AtomicInteger	AtomicIntegerArray	AtomicLong
AtomicLongArray	AtomicLongFieldUpdater	AtomicMarkableReference	AtomicReference
AtomicReferenceArray	AtomicReferenceFieldUpdater	AtomicStampedReference	Fences

java.util.concurrent.locks

AbstractOwnableSynchronizer	AbstractQueuedLongSynchronizer	AbstractQueuedSynchronizer	Condition
Lock	LockSupport	ReadWriteLock	ReentrantLock
ReentrantReadWriteLock

java.util.logging

ConsoleHandler	ErrorManager	Filter	Formatter
Handler	Level	LogManager	LogRecord
Logger	LoggingMXBean	LoggingPermission	MemoryHandler
SimpleFormatter	StreamHandler	XMLFormatter

java.util.regex

MatchResult	Matcher	Pattern	PatternSyntaxException
Splitter

javax.xml

XMLConstants

javax.xml.parsers

FactoryConfigurationError	FilePathToURI	ParserConfigurationException	SAXParser
SAXParserFactory

javax.xml.transform

Result

Source

javax.xml.validation

Schema

TypeInfoProvider

Validator

ValidatorHandler

org.w3c.dom

TypeInfo

org.w3c.dom.ls

LSInput

LSResourceResolver

org.xml.sax

AttributeList	Attributes	ContentHandler	DocumentHandler
DTDHandler	EntityResolver	ErrorHandler	HandlerBase
InputSource	Locator	Parser	SAXException
SAXNotRecognizedException	SAXNotSupportedException	SAXParseException	XMLFilter
XMLReader

org.xml.sax.ext

Attributes2	Attributes2Impl	DeclHandler	DefaultHandler2
EntityResolver2	LexicalHandler	Locator2	Locator2Impl

org.xml.sax.helpers

AttributeListImpl	AttributesImpl	DefaultHandler	LocatorImpl
NamespaceSupport	ParserAdapter	ParserFactory	XMLFilterImpl
XMLReaderAdapter	XMLReaderFactory