org.safs.persist

Class PersistorToString

java.lang.Object

org.safs.persist.PersistableChecker

org.safs.persist.AbstractPersistor

org.safs.persist.PersistorToString

All Implemented Interfaces:

Persistor

Direct Known Subclasses:

PersistorToHierarchialString

public abstract class PersistorToString
extends AbstractPersistor

This class is used to convert a Persistable object to a string and convert a string to a Persistable object.
The string format will depends on the sub-class's implementation.

Author:

Lei Wang

Field Summary

Fields

Modifier and Type	Field and Description
protected java.util.Map<java.lang.String,java.util.List<java.lang.String>>	ignoredFieldsForUnpickle Holding the fields which are ignored for each class.
protected java.lang.StringBuilder	stringFormat The string format of a Persistable object.
protected java.io.Reader	stringFormatReader The Reader containing string format of a Persistable object.

Constructor Summary

Constructors

Constructor and Description
PersistorToString()
PersistorToString(java.io.Reader stringFormatReader)
PersistorToString(java.lang.String stringFormat)

Method Summary

Modifier and Type	Method and Description
protected void	beforeUnpickle() Prepare the parser with the string format of a Persistable object.
protected Persistable	doUnpickle() Convert the string format of a Persistable object to Persistable object.
protected java.lang.String	escape(java.lang.String value) When writing a string to a file, some special characters MUST be escaped, such as new line "\n", "\r", "\r\n", or double quote ", or <?XML>...</XML> etc. What characters to escape and how to escape, these depend on the format of the persistence file, and the parser of the file.
java.lang.String	getPersistenceName() The name of the persistence material holding the content of an Object. It can be a file name or a variable name etc. It could be useful when deleting the persistence.
java.lang.String	getStringFormat()
java.io.Reader	getStringFormatReader()
PersistenceType	getType() The persistence Type.
protected boolean	isIgnoredField(java.lang.String className, java.lang.String field) Check if the field is being ignored at the moment for un-pickle.
protected abstract java.lang.String	parse(Persistable persistable, boolean needLeadingNameForContainer) Convert a Persistable Object to a string.
void	persist(Persistable persistable) Persist a Persistable object.
void	setStringFormat(java.lang.String stringFormat)
void	setStringFormatReader(java.io.Reader stringFormatReader)
protected boolean	stringNeedQuoted() If the string value needs to be quoted before writing into a kind of persistence. JSON file requires that for string value. In JSON file, For example: "key" : "stringValue" is good "key" : stringValue is bad
void	unpersist() Try to delete a persistence StringBuffer.
Persistable	unpickle(java.util.Map<java.lang.String,java.util.List<java.lang.String>> ignoredFields) Provided default implementation, simply throw out a SAFSException.
protected void	write(Persistable persistable) Write the Persistable object into a persistent material. writeHeader(Persistable) is called before writeTailer(Persistable) is called after
protected void	writeHeader(Persistable persistable) This is called before write(Persistable).
protected void	writeTailer(Persistable persistable) This is called after write(Persistable).

Methods inherited from class org.safs.persist.PersistableChecker

validate

Methods inherited from class java.lang.Object

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

Field Detail

stringFormat

protected java.lang.StringBuilder stringFormat

The string format of a Persistable object. The concrete format will depend on the sub-class's implementation.

stringFormatReader

protected java.io.Reader stringFormatReader

The Reader containing string format of a Persistable object.

See Also:

stringFormat

ignoredFieldsForUnpickle

protected java.util.Map<java.lang.String,java.util.List<java.lang.String>> ignoredFieldsForUnpickle

Holding the fields which are ignored for each class. No need to unpickle.
The field is expressed as a pair of (classname, a list of fields).

See Also:

#isIgnoredFiled(String)

Constructor Detail

PersistorToString

public PersistorToString()

PersistorToString

public PersistorToString(java.lang.String stringFormat)

PersistorToString

public PersistorToString(java.io.Reader stringFormatReader)

Method Detail

getStringFormat

public java.lang.String getStringFormat()

Returns:

the stringFormat of a Persistable object.

setStringFormat

public void setStringFormat(java.lang.String stringFormat)

Parameters:

stringFormat - the stringFormat of a Persistable object.

getStringFormatReader

public java.io.Reader getStringFormatReader()

Returns:

Reader, the stringFormatReader. It can be null.

setStringFormatReader

public void setStringFormatReader(java.io.Reader stringFormatReader)

Parameters:

stringFormatReader - the stringFormatReader to set

persist

public void persist(Persistable persistable)
             throws SAFSException

Description copied from interface: Persistor

Persist a Persistable object.

Specified by:

persist in interface Persistor

Overrides:

persist in class AbstractPersistor

Parameters:

persistable - Persistable, the object to persist

Throws:

SAFSException - when persistence fails or something wrong happens.

writeHeader

protected void writeHeader(Persistable persistable)
                    throws SAFSException

This is called before write(Persistable).

Throws:

SAFSException

write

protected final void write(Persistable persistable)
                    throws SAFSException

Write the Persistable object into a persistent material.
writeHeader(Persistable) is called before
writeTailer(Persistable) is called after

Throws:

SAFSException

writeTailer

protected void writeTailer(Persistable persistable)
                    throws SAFSException

This is called after write(Persistable).

Throws:

SAFSException

stringNeedQuoted

protected boolean stringNeedQuoted()

If the string value needs to be quoted before writing into a kind of persistence.
JSON file requires that for string value.
In JSON file, For example:
"key" : "stringValue" is good
"key" : stringValue is bad

Returns:

boolean true if the value needs to be quoted before writing into persistence.

escape

protected java.lang.String escape(java.lang.String value)

When writing a string to a file, some special characters MUST be escaped, such as new line "\n", "\r", "\r\n", or double quote ", or <?XML>...</XML> etc.
What characters to escape and how to escape, these depend on the format of the persistence file, and the parser of the file. Subclass should override this method.
This method will also quote the value if stringNeedQuoted() returns true.

Parameters:

value - String, the value to escape.

Returns:

String, the escaped string

See Also:

stringNeedQuoted()

unpersist

public void unpersist()
               throws SAFSException

Try to delete a persistence StringBuffer.

Specified by:

unpersist in interface Persistor

Overrides:

unpersist in class AbstractPersistor

Throws:

SAFSException - when failing to delete the persistence or something wrong happens.

unpickle

public Persistable unpickle(java.util.Map<java.lang.String,java.util.List<java.lang.String>> ignoredFields)
                     throws SAFSException

Description copied from class: AbstractPersistor

Provided default implementation, simply throw out a SAFSException.

Specified by:

unpickle in interface Persistor

Overrides:

unpickle in class AbstractPersistor

Parameters:

ignoredFields - Map<String, List<String>>, a Map containing the fields of each class to be ignored when un-pickling.

Returns:

Persistable, the Persistable object got from the persistence material.

Throws:

SAFSException

beforeUnpickle

protected void beforeUnpickle()
                       throws SAFSException

Prepare the parser with the string format of a Persistable object.

Throws:

SAFSException

doUnpickle

protected Persistable doUnpickle()
                          throws SAFSException

Convert the string format of a Persistable object to Persistable object.

Returns:

Persistable, the Persistable object.

Throws:

SAFSException

parse

protected abstract java.lang.String parse(Persistable persistable,
                                          boolean needLeadingNameForContainer)
                                   throws SAFSException

Convert a Persistable Object to a string. The concrete format depends on the sub-class.

Parameters:

persistable -

needLeadingNameForContainer -

Returns:

Throws:

SAFSException

isIgnoredField

protected boolean isIgnoredField(java.lang.String className,
                                 java.lang.String field)

Check if the field is being ignored at the moment for un-pickle.

Parameters:

className - String, the className to check

field - String, the field to check

Returns:

boolean if this field is being ignored.

See Also:

ignoredFieldsForUnpickle

getType

public PersistenceType getType()

Description copied from interface: Persistor

The persistence Type.

Returns:

PersistenceType

getPersistenceName

public java.lang.String getPersistenceName()

Description copied from interface: Persistor

The name of the persistence material holding the content of an Object.
It can be a file name or a variable name etc.
It could be useful when deleting the persistence.

Returns:

String, The name of the persistence material, such as the file name or the variable name etc.

See Also:

Persistor.unpersist()