au.com.cybersearch2.example

Class HelloTwoDbsMain

java.lang.Object

au.com.cybersearch2.example.HelloTwoDbsMain

public class HelloTwoDbsMain
extends Object

ORIGINAL COMMENTS: This is an application similar to HelloAndroid but it supports two databases and manages the helper on its own. CLASSYTOOLS COMMENTS: This version shows supporting two databases requires no more than placing two persistence units in the persistence.xml configuration file. Each persistence unit is then referenced in the code by name. To support version upgrades, this application also includes a database version stored in a "User_Info" table on each database - see test java au.com.cybersearch2.example.v2.HelloTwoDbsMain. Also demonstrated is the important principle of layering an application to separate concerns. Porting the code to Android requires only changing the dependency injection configuration. See project "AndroidHelloTwoDbs".

Field Summary

Fields

Modifier and Type	Field and Description
static String	ALL_COMPLEX_DATA Named query to find all ComplexData objects
static String	ALL_SIMPLE_DATA Named query to find all SimpleData objects
static String	DATABASE_INFO_NAME
static String	PU_NAME1
static String	PU_NAME2
static Object	SEPARATOR_LINE
static String	TAG

Constructor Summary

Constructors

Constructor and Description
HelloTwoDbsMain() Create HelloTwoDbsMain object This creates and populates the database using JPA and runs a test from main().

Method Summary

Methods

Modifier and Type	Method and Description
void	clearDatabaseTables() Clear database tables if they exist
void	displayMessage(String message) Display message to user
void	dropDatabaseTables()
void	dropDatabaseVersionTable(String puName)
static void	logInfo(String tag, String message) Public accessor for logMessage()
void	logMessage(String tag, String message) Log message
static void	main(String[] args) Test 2 Databases accessed by application
void	performPersistenceWork(String puName, PersistenceTask persistenceTask) Launch persistence work to run in background thread and wait for completion
void	populateDatabases() Populate databases with initial sample data
void	setUp() Populate entity tables.
void	setUp(boolean fromStart)
void	shutdown()

Methods inherited from class java.lang.Object

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

Field Detail

TAG

public static final String TAG

See Also:

Constant Field Values

PU_NAME1

public static final String PU_NAME1

See Also:

Constant Field Values

PU_NAME2

public static final String PU_NAME2

See Also:

Constant Field Values

ALL_SIMPLE_DATA

public static final String ALL_SIMPLE_DATA

Named query to find all SimpleData objects

See Also:

Constant Field Values

ALL_COMPLEX_DATA

public static final String ALL_COMPLEX_DATA

Named query to find all ComplexData objects

See Also:

Constant Field Values

DATABASE_INFO_NAME

public static final String DATABASE_INFO_NAME

See Also:

Constant Field Values

SEPARATOR_LINE

public static final Object SEPARATOR_LINE

Constructor Detail

HelloTwoDbsMain

public HelloTwoDbsMain()

Create HelloTwoDbsMain object This creates and populates the database using JPA and runs a test from main().

Method Detail

main

public static void main(String[] args)

Test 2 Databases accessed by application

Parameters:

args - Not used

setUp

public void setUp()
           throws InterruptedException

Populate entity tables. Call this before doing any queries. Note the calling thread is suspended while the work is performed on a background thread.

Throws:

InterruptedException

setUp

public void setUp(boolean fromStart)
           throws InterruptedException

Throws:

InterruptedException

shutdown

public void shutdown()

performPersistenceWork

public void performPersistenceWork(String puName,
                          PersistenceTask persistenceTask)
                            throws InterruptedException

Launch persistence work to run in background thread and wait for completion

Parameters:

puName - Persistence Unit name

persistenceTask - PersistenceTask object

Throws:

InterruptedException

logMessage

public void logMessage(String tag,
              String message)

Log message

Parameters:

tag -

message -

displayMessage

public void displayMessage(String message)

Display message to user

Parameters:

message -

clearDatabaseTables

public void clearDatabaseTables()
                         throws InterruptedException

Clear database tables if they exist

Throws:

InterruptedException

dropDatabaseTables

public void dropDatabaseTables()
                        throws InterruptedException

Throws:

InterruptedException

dropDatabaseVersionTable

public void dropDatabaseVersionTable(String puName)
                              throws InterruptedException

Throws:

InterruptedException

populateDatabases

public void populateDatabases()
                       throws InterruptedException

Populate databases with initial sample data

Throws:

InterruptedException

logInfo

public static void logInfo(String tag,
           String message)

Public accessor for logMessage()

Parameters:

tag -

message -