Package com.tagtraum.core

Class JsonDB<T>

java.lang.Object

com.tagtraum.core.JsonDB<T>

public class JsonDB<T>
extends Object

Very simple JSON-based store for beans with only strings, booleans and numbers as well as simple Lists, Sets and Maps of those types as property values. This DB always simply appends a line at the end, when an bean is added. Therefore adding is very cheap.

Author:

Hendrik Schreiber

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	JsonDB.ExceptionListener	Simple exception listener to handle problems while parsing a individual bean.

Constructor Summary

Constructors

Constructor	Description
JsonDB(Path file)	JsonDb, creates the database file, if it does not exist yet.

Method Summary

Modifier and Type	Method	Description
void	add(T bean)	Adds a bean to the DB.
void	addAll(Collection<T> beans)	Bulk adds beans to the DB.
void	clear()	Deletes the database file.
JsonDB.ExceptionListener	getExceptionListener()
Path	getFile()
void	read(Collection<T> collection)	Adds all elements to the given collection.
boolean	remove(Object bean)	Removes an object from the database.
void	setExceptionListener(JsonDB.ExceptionListener exceptionListener)

Methods inherited from class java.lang.Object

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

Constructor Detail

JsonDB

public JsonDB(Path file)

JsonDb, creates the database file, if it does not exist yet.

Parameters:

file - database file

Method Detail

getFile

public Path getFile()

getExceptionListener

public JsonDB.ExceptionListener getExceptionListener()

setExceptionListener

public void setExceptionListener(JsonDB.ExceptionListener exceptionListener)

read

public void read(Collection<T> collection)
          throws IOException

Adds all elements to the given collection.

Parameters:

collection - collection

Throws:

IOException

add

public void add(T bean)
         throws IOException

Adds a bean to the DB.

Parameters:

bean - bean

Throws:

IOException

addAll

public void addAll(Collection<T> beans)
            throws IOException

Bulk adds beans to the DB.

Parameters:

beans - beans

Throws:

IOException

remove

public boolean remove(Object bean)
               throws IOException

Removes an object from the database. Note that we do not compare with Object.equals(Object), but simply compare the JSON strings.

Parameters:

bean - bean

Returns:

true, if the bean was found and removed

Throws:

IOException

clear

public void clear()
           throws IOException

Deletes the database file.

Throws:

IOException