OpenJDK 1.22 · java.io.ObjectStreamClass · APIdia, the JavaDoc alternative

Modifier and Type	Class and Description
private static class	ObjectStreamClass.Caches
pack-priv static class	ObjectStreamClass.ClassDataSlot Class representing the portion of an object's serialized form allotted to data described by a given class descriptor.
private static class	ObjectStreamClass.DeserializationConstructorsCache A LRA cache of record deserialization constructors.
private static class	ObjectStreamClass.ExceptionInfo Contains information about InvalidClassException instances to be thrown when attempting operations on an invalid class.
private static class	ObjectStreamClass.FieldReflector Class for setting and retrieving serializable field values in batch.
private static class	ObjectStreamClass.FieldReflectorKey FieldReflector cache lookup key.
private static class	ObjectStreamClass.MemberSignature Class for computing and caching field/constructor/method signatures during serialVersionUID calculation.
pack-priv static class	ObjectStreamClass.RecordSupport Record specific support for retrieving and binding stream field values.

Field Summary

Modifier and Type	Field and Description
private MethodHandle	canonicalCtr record canonical constructor (shared among OSCs for same class), or null
private Class<?>	cl class associated with this descriptor (if any)
private Constructor<?>	cons serialization-appropriate constructor, or null if none
private volatile ObjectStreamClass.ClassDataSlot[]	dataLayout data layout of serialized objects described by this class desc
private ObjectStreamClass.ExceptionInfo	defaultSerializeEx exception (if any) to throw if default serialization attempted
private MethodHandle	deserializationCtr session-cache of record deserialization constructor (in de-serialized OSC only), or null
private ObjectStreamClass.DeserializationConstructorsCache	deserializationCtrs cache of record deserialization constructors per unique set of stream fields (shared among OSCs for same class), or null
private ObjectStreamClass.ExceptionInfo	deserializeEx exception (if any) to throw if non-enum deserialization attempted
private ProtectionDomain[]	domains protection domains that need to be checked when calling the constructor
private boolean	externalizable true if represented class implements Externalizable
private ObjectStreamClass.FieldReflector	fieldRefl reflector for setting/getting serializable field values
private ObjectStreamField[]	fields serializable fields
private boolean	hasBlockExternalData true if desc has externalizable data written in block data format; this must be true by default to accommodate ObjectInputStream subclasses which override readClassDescriptor() to return class descriptors obtained from ObjectStreamClass.lookup() (see 4461737)
private boolean	hasWriteObjectData true if desc has data written by class-defined writeObject method
private boolean	initialized true if, and only if, the object has been correctly initialized
private boolean	isEnum true if represents enum type
private boolean	isProxy true if represents dynamic proxy class
private boolean	isRecord true if represents record type
private ObjectStreamClass	localDesc local class descriptor for represented class (may point to self)
private String	name name of class represented by this descriptor
public static final ObjectStreamField[]	NO_FIELDS serialPersistentFields value indicating no serializable fields
private int	numObjFields number of non-primitive fields
private int	primDataSize aggregate marshalled size of primitive fields
private Method	readObjectMethod class-defined readObject method, or null if none
private Method	readObjectNoDataMethod class-defined readObjectNoData method, or null if none
private Method	readResolveMethod class-defined readResolve method, or null if none
private static final ReflectionFactory	reflFactory reflection factory for obtaining serialization constructors
private ClassNotFoundException	resolveEx exception (if any) thrown while attempting to resolve class
private boolean	serializable true if represented class implements Serializable
private ObjectStreamClass.ExceptionInfo	serializeEx exception (if any) to throw if non-enum serialization attempted
private static final ObjectStreamField[]	serialPersistentFields `ObjectStreamClass` has no fields for default serialization.
private static final long	serialVersionUID
private volatile Long	suid serialVersionUID of represented class (null if not computed yet)
private ObjectStreamClass	superDesc superclass descriptor appearing in stream
private Method	writeObjectMethod class-defined writeObject method, or null if none
private Method	writeReplaceMethod class-defined writeReplace method, or null if none

Access	Constructor and Description
private	ObjectStreamClass(final Class<?> cl) Creates local class descriptor representing given class.
pack-priv	ObjectStreamClass() Creates blank class descriptor which should be initialized via a subsequent call to initProxy(), initNonProxy() or readNonProxy().

Method Summary

Modifier and Type	Method and Description
private static MethodHandle	canonicalRecordCtr(Class<?> cls) Returns the canonical constructor for the given record class, or null if the not found ( which should never happen for correctly generated record classes ).
pack-priv void	checkDefaultSerialize() Throws an InvalidClassException if objects whose class is represented by this descriptor should not be permitted to use default serialization (e.g., if the class declares serializable fields that do not correspond to actual fields, and hence must use the GetField API).
pack-priv void	checkDeserialize() Throws an InvalidClassException if object instances referencing this class descriptor should not be allowed to deserialize.
pack-priv final void	checkInitialized() Throws InvalidClassException if not initialized.
pack-priv void	checkObjFieldValueTypes(Object obj, Object[] vals) Checks that the given values, from array vals starting at offset 0, are assignable to the given serializable object fields.
pack-priv void	checkSerialize() Throws an InvalidClassException if objects whose class is represented by this descriptor should not be allowed to serialize.
private static boolean	classNamesEqual(String name1, String name2) Compares class names for equality, ignoring package names.
private static long	computeDefaultSUID(Class<?> cl) Computes the default serial version UID value for the given class.
private void	computeFieldOffsets() Calculates and sets serializable field offsets, as well as primitive data size and object field count totals.
public Class<?>	Returns: the `Class` instance that this descriptor represents forClass() Return the class in the local VM that this version is mapped to.
pack-priv ObjectStreamClass.ClassDataSlot[]	getClassDataLayout() Returns array of ClassDataSlot instances representing the data layout (including superclass data) for serialized objects described by this class descriptor.
private ObjectStreamClass.ClassDataSlot[]	getClassDataLayout0()
private static ObjectStreamField[]	getDeclaredSerialFields(Class<?> cl) Returns serializable fields of given class as defined explicitly by a "serialPersistentFields" field, or null if no appropriate "serialPersistentFields" field is defined.
private static Long	getDeclaredSUID(Class<?> cl) Returns explicit serial version UID value declared by given class, or null if none.
private static ObjectStreamField[]	getDefaultSerialFields(Class<?> cl) Returns array of ObjectStreamFields corresponding to all non-static non-transient fields declared by given class.
private static Constructor<?>	getExternalizableConstructor(Class<?> cl) Returns public no-arg constructor of given class, or null if none found.
public ObjectStreamField	Returns: The ObjectStreamField object of the named field or null if there is no such named field. getField(String the name of the data field to look for name) Get the field of this class by name.
pack-priv ObjectStreamField	getField(String name, Class<?> type) Looks up a serializable field of the represented class by name and type.
public ObjectStreamField[]	Returns: an array containing an element for each persistent field of this class. Returns an array of length zero if there are no fields. getFields() Return an array of the fields of this serializable class.
pack-priv ObjectStreamField[]	getFields(boolean copy) Returns arrays of ObjectStreamFields representing the serializable fields of the represented class.
private static Method	getInheritableMethod(Class<?> cl, String name, Class<?>[] argTypes, Class<?> returnType) Returns non-static, non-abstract method with given signature provided it is defined by or accessible (via inheritance) by the given class, or null if no match found.
pack-priv ObjectStreamClass	getLocalDesc() Returns the "local" class descriptor for the class associated with this class descriptor (i.e., the result of ObjectStreamClass.lookup(this.forClass())) or null if there is no class associated with this descriptor.
private static String	getMethodSignature(Class<?>[] paramTypes, Class<?> retType) Returns JVM type signature for given list of parameters and return type.
public String	Returns: a string representing the name of the class getName() Returns the name of the class described by this descriptor.
pack-priv int	getNumObjFields() Returns number of non-primitive serializable fields of represented class.
pack-priv void	getObjFieldValues(Object obj, Object[] vals) Fetches the serializable object field values of object obj and stores them in array vals starting at offset 0.
pack-priv int	getPrimDataSize() Returns aggregate size (in bytes) of marshalled primitive field values for represented class.
pack-priv void	getPrimFieldValues(Object obj, byte[] buf) Fetches the serializable primitive field values of object obj and marshals them into byte array buf starting at offset 0.
private static Method	getPrivateMethod(Class<?> cl, String name, Class<?>[] argTypes, Class<?> returnType) Returns non-static private method with given signature defined by given class, or null if none found.
private ProtectionDomain[]	Returns: An array of ProtectionDomain representing the set of ProtectionDomain that separate the concrete class `cl` from its ancestor's declaring `cons`, or `null`. getProtectionDomains(Constructor<?> A constructor declared by `cl` or one of its ancestors. cons, Class<?> A concrete class, which is either the class declaring the constructor `cons`, or a serializable subclass of that class. cl) Aggregate the ProtectionDomains of all the classes that separate a concrete class `cl` from its ancestor's class declaring a constructor `cons`.
pack-priv MethodHandle	getRecordConstructor() Returns the canonical constructor, if the local class equivalent of this stream class descriptor is a record class, otherwise null.
private static ObjectStreamClass.FieldReflector	getReflector(ObjectStreamField[] fields, ObjectStreamClass localDesc) Matches given set of serializable fields with serializable fields described by the given local class descriptor, and returns a FieldReflector instance capable of setting/getting values from the subset of fields that match (non-matching fields are treated as filler, for which get operations return default values and set operations discard given values).
pack-priv ClassNotFoundException	getResolveException() Returns ClassNotFoundException (if any) thrown while attempting to resolve local class corresponding to this class descriptor.
private static ObjectStreamField[]	getSerialFields(Class<?> cl) Returns ObjectStreamField array describing the serializable fields of the given class.
private static Constructor<?>	getSerializableConstructor(Class<?> cl) Returns subclass-accessible no-arg constructor of first non-serializable superclass, or null if none found.
public long	Returns: the SUID of the class described by this descriptor getSerialVersionUID() Return the serialVersionUID for this class.
pack-priv ObjectStreamClass	getSuperDesc() Returns superclass descriptor.
private ObjectStreamClass	getVariantFor(Class<?> cl) If given class is the same as the class associated with this class descriptor, returns reference to this class descriptor.
pack-priv boolean	hasBlockExternalData() Returns true if class descriptor represents externalizable class that has written its data in 1.2 (block data) format, false otherwise.
pack-priv boolean	hasReadObjectMethod() Returns true if represented class is serializable (but not externalizable) and defines a conformant readObject method.
pack-priv boolean	hasReadObjectNoDataMethod() Returns true if represented class is serializable (but not externalizable) and defines a conformant readObjectNoData method.
pack-priv boolean	hasReadResolveMethod() Returns true if represented class is serializable or externalizable and defines a conformant readResolve method.
private static native boolean	hasStaticInitializer(Class<?> cl) Returns true if the given class defines a static initializer method, false otherwise.
pack-priv boolean	hasWriteObjectData() Returns true if class descriptor represents serializable (but not externalizable) class which has written its data via a custom writeObject() method, false otherwise.
pack-priv boolean	hasWriteObjectMethod() Returns true if represented class is serializable (but not externalizable) and defines a conformant writeObject method.
pack-priv boolean	hasWriteReplaceMethod() Returns true if represented class is serializable or externalizable and defines a conformant writeReplace method.
private static native void	initNative() Initializes native code.
pack-priv void	initNonProxy(ObjectStreamClass model, Class<?> cl, ClassNotFoundException resolveEx, ObjectStreamClass superDesc) Initializes class descriptor representing a non-proxy class.
pack-priv void	initProxy(Class<?> cl, ClassNotFoundException resolveEx, ObjectStreamClass superDesc) Initializes class descriptor representing a proxy class.
pack-priv void	invokeReadObject(Object obj, ObjectInputStream in) Invokes the readObject method of the represented serializable class.
pack-priv void	invokeReadObjectNoData(Object obj) Invokes the readObjectNoData method of the represented serializable class.
pack-priv Object	invokeReadResolve(Object obj) Invokes the readResolve method of the represented serializable class and returns the result.
pack-priv void	invokeWriteObject(Object obj, ObjectOutputStream out) Invokes the writeObject method of the represented serializable class.
pack-priv Object	invokeWriteReplace(Object obj) Invokes the writeReplace method of the represented serializable class and returns the result.
pack-priv boolean	isEnum() Returns true if class descriptor represents an enum type, false otherwise.
pack-priv boolean	isExternalizable() Returns true if represented class implements Externalizable, false otherwise.
pack-priv boolean	isInstantiable() Returns true if represented class is serializable/externalizable and can be instantiated by the serialization runtime--i.e., if it is externalizable and defines a public no-arg constructor, or if it is non-externalizable and its first non-serializable superclass defines an accessible no-arg constructor.
pack-priv boolean	isProxy() Returns true if class descriptor represents a dynamic proxy class, false otherwise.
pack-priv boolean	isRecord() Returns true if class descriptor represents a record type, false otherwise.
pack-priv boolean	isSerializable() Returns true if represented class implements Serializable, false otherwise.
public static ObjectStreamClass	Returns: the class descriptor for the specified class lookup(Class<?> class for which to get the descriptor cl) Find the descriptor for a class that can be serialized.
pack-priv static ObjectStreamClass	lookup(Class<?> class to look up cl, boolean if true, return descriptors for all classes; if false, only return descriptors for serializable classes all) Looks up and returns class descriptor for given class, or null if class is non-serializable and "all" is set to false.
public static ObjectStreamClass	Returns: the class descriptor for the specified class lookupAny(Class<?> class for which to get the descriptor cl) Returns the descriptor for any class, regardless of whether it implements `Serializable`.
private static ObjectStreamField[]	matchFields(ObjectStreamField[] fields, ObjectStreamClass localDesc) Matches given set of serializable fields with serializable fields obtained from the given local class descriptor (which contain bindings to reflective Field objects).
pack-priv Object	newInstance() Creates a new instance of the represented class.
private ProtectionDomain	noPermissionsDomain() Creates a PermissionDomain that grants no permission.
private static boolean	packageEquals(Class<?> cl1, Class<?> cl2) Returns true if classes are defined in the same runtime package, false otherwise.
pack-priv void	readNonProxy(ObjectInputStream in) Reads non-proxy class descriptor information from given input stream.
private final void	requireInitialized() Throws InternalError if not initialized.
pack-priv void	setObjFieldValues(Object obj, Object[] vals) Sets the serializable object fields of object obj using values from array vals starting at offset 0.
pack-priv void	setPrimFieldValues(Object obj, byte[] buf) Sets the serializable primitive fields of object obj using values unmarshalled from byte array buf starting at offset 0.
private static void	throwMiscException(Throwable th) Convenience method for throwing an exception that is either a RuntimeException, Error, or of some unexpected type (in which case it is wrapped inside an IOException).
public String	toString() Overrides java.lang.Object.toString. Return a string describing this ObjectStreamClass.
pack-priv void	writeNonProxy(ObjectOutputStream out) Writes non-proxy class descriptor information to given output stream.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

public final Class ObjectStreamClass

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary