com.sleepycat.persist.impl
Class EnumFormat

java.lang.Object
  com.sleepycat.persist.impl.Format
      com.sleepycat.persist.impl.EnumFormat

All Implemented Interfaces:

RawType, Serializable

public class EnumFormat
extends Format

Format for all enum types. In this class we resort to using reflection to allocate arrays of enums. If there is a need for it, reflection could be avoided in the future by generating code as new array formats are encountered.

Author:

Mark Hayes

See Also:

Serialized Form

Field Summary

Fields inherited from class com.sleepycat.persist.impl.Format

ID_BIGDEC, ID_BIGINT, ID_BOOL, ID_BOOL_W, ID_BYTE, ID_BYTE_W, ID_CHAR, ID_CHAR_W, ID_DATE, ID_DOUBLE, ID_DOUBLE_W, ID_FLOAT, ID_FLOAT_W, ID_INT, ID_INT_W, ID_LONG, ID_LONG_W, ID_NULL, ID_OBJECT, ID_PREDEFINED, ID_SHORT, ID_SHORT_W, ID_SIMPLE_MAX, ID_SIMPLE_MIN, ID_STRING

Constructor Summary

EnumFormat(Class type)

Method Summary

(package private) void	collectRelatedFormats(Catalog catalog, Map<String,Format> newFormats) Calls catalog.createFormat for formats that this format depends on, or that should also be persistent.
boolean	equals(Object other) Used to compare the current version and an old version, to determine whether class evolution is needed.
List<String>	getEnumConstants() Returns an unmodifiable list of the names of the enum instances, or null if this is not an enum type.
(package private) void	initialize(Catalog catalog) Initializes an uninitialized format, initializing its related formats (superclass formats and array component formats) first.
boolean	isEnum() Returns whether this is an enum type.
(package private) Object	newArray(int len) Creates an array of the format's class of the given length, as if Array.newInstance(getType(), len) were called.
(package private) Object	newInstance(EntityInput input, boolean rawAccess) Creates a new instance of the target class using its default constructor.
(package private) void	readObject(Object o, EntityInput input, boolean rawAccess) Called after newInstance() to read the rest of the data bytes and fill in the object contents.
(package private) void	skipContents(EntityInput input) Skips over the object's contents, as if readObject() were called, but without returning an object.
(package private) void	writeObject(Object o, EntityOutput output, boolean rawAccess) Writes a given instance of the target class to the output data bytes.

Methods inherited from class com.sleepycat.persist.impl.Format

copySecKey, copySecMultiKey, evolveTo, getClassMetadata, getClassName, getComponentType, getDimensions, getEntityFormat, getEntityMetadata, getFields, getId, getProxiedFormat, getSuperFormat, getSuperType, getType, getVersion, getWrapperFormat, initializeIfNeeded, isArray, isAssignableTo, isCurrentVersion, isEntity, isModelClass, isPredefined, isPriKeyNullOrZero, isPrimitive, isSimple, nullifySecKey, readPriKey, setId, setProxiedFormat, setSuperFormat, skipToSecKey, writePriKey

Methods inherited from class java.lang.Object

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

Constructor Detail

EnumFormat

EnumFormat(Class type)

Method Detail

isEnum

public boolean isEnum()

Description copied from interface: RawType

Returns whether this is an enum type.

If true is returned, a value of this type is a RawObject and the enum constant String is available via RawObject.getEnum().

If false is returned, then this is a complex type, an array type (see RawType.isArray()), or a simple type (see RawType.isSimple()).

Specified by:

isEnum in interface RawType

Overrides:

isEnum in class Format

getEnumConstants

public List<String> getEnumConstants()

Description copied from interface: RawType

Returns an unmodifiable list of the names of the enum instances, or null if this is not an enum type.

Specified by:

getEnumConstants in interface RawType

Overrides:

getEnumConstants in class Format

collectRelatedFormats

void collectRelatedFormats(Catalog catalog,
                           Map<String,Format> newFormats)

Description copied from class: Format

Calls catalog.createFormat for formats that this format depends on, or that should also be persistent.

Specified by:

collectRelatedFormats in class Format

initialize

void initialize(Catalog catalog)

Description copied from class: Format

Initializes an uninitialized format, initializing its related formats (superclass formats and array component formats) first.

Specified by:

initialize in class Format

newArray

Object newArray(int len)

Description copied from class: Format

Creates an array of the format's class of the given length, as if Array.newInstance(getType(), len) were called. Formats implement this method for specific classes, or call the accessor, to avoid the reflection overhead of Array.newInstance.

Specified by:

newArray in class Format

newInstance

Object newInstance(EntityInput input,
                   boolean rawAccess)

Description copied from class: Format

Creates a new instance of the target class using its default constructor. Normally this creates an empty object, and readObject() is called next to fill in the contents. This is done in two steps to allow the instance to be registered by EntityInput before reading the contents. This allows the fields in an object or a nested object to refer to the parent object in a graph. Alternatively, this method may read all or the first portion of the data, rather than that being done by readObject(). This is required for simple types and enums, where the object cannot be created without reading the data. In these cases, there is no possibility that the parent object will be referenced by the child object in the graph. It should not be done in other cases, or the graph references may not be maintained faithfully.

Specified by:

newInstance in class Format

writeObject

void writeObject(Object o,
                 EntityOutput output,
                 boolean rawAccess)

Description copied from class: Format

Writes a given instance of the target class to the output data bytes. This is the complement of the newInstance()/readObject() pair.

Specified by:

writeObject in class Format

readObject

void readObject(Object o,
                EntityInput input,
                boolean rawAccess)

Description copied from class: Format

Called after newInstance() to read the rest of the data bytes and fill in the object contents. If the object was read completely by newInstance(), this method does nothing.

Specified by:

readObject in class Format

skipContents

void skipContents(EntityInput input)

Description copied from class: Format

Skips over the object's contents, as if readObject() were called, but without returning an object. Used for extracting secondary key bytes without having to instantiate the object. For reference types, the format ID is read just before calling this method, so this method is responsible for skipping everything following the format ID.

Specified by:

skipContents in class Format

equals

public boolean equals(Object other)

Description copied from class: Format

Used to compare the current version and an old version, to determine whether class evolution is needed. Subclasses should always override this method and also call super.equals() as part of their comparison.

Overrides:

equals in class Format