package com.oreilly.jent.ejb.containerManaged;
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*
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*
* "Java Enterprise in a Nutshell, Third Edition,
* by Jim Farley and William Crawford
* with Prakash Malani, John G. Norman, and Justin Gehtland.
* Copyright 2006 O'Reilly Media, Inc., 0-596-10142-2."
*
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import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.Properties;
import javax.ejb.CreateException;
import javax.ejb.EJBException;
import javax.ejb.EntityBean;
import javax.ejb.EntityContext;
import com.oreilly.jent.ejb.NoSuchPersonException;
abstract public class ProfileBean implements EntityBean {
//--------------------------------------------------
// Persistent data properties
//--------------------------------------------------
// EJB 2.x: Just provide abstract accessors for the properties
// Name of the person owning the profile
abstract public String getName();
abstract public void setName(String name);
// Serialized representation of profile entries, for storage in persistent
// store, or passivated state
abstract public byte[] getEntriesBytes();
abstract public void setEntriesBytes(byte[] entries);
// EJB 1.1: Define actual data members to hold persistent data
// Name of the person owning the profile
//public String mName = "";
// Serialized representation of profile entries, for storage in persistent
// store, or passivated state
//public byte[] mEntriesBytes = null;
// Entries in the profile (name/value pairs)
transient private Properties mEntries = new Properties();
// Our entity context
private EntityContext mContext = null;
//--------------------------------------------------
// Utility methods
//--------------------------------------------------
// Transfer the list of entries from our Properties member to the byte
// array.
private void transferToBytes() throws IOException {
// Serialize the Properties into a byte array using an ObjectOutputStream
if (mEntries != null) {
ByteArrayOutputStream byteOut = new ByteArrayOutputStream();
ObjectOutputStream objOut = new ObjectOutputStream(byteOut);
objOut.writeObject(mEntries);
setEntriesBytes(byteOut.toByteArray());
}
}
// Convert the serialized byte array into our Properties entry list.
private void transferToProps() throws IOException {
// Take the raw byte array and de-serialize it
// back into a Properties object using an ObjectInputStream
try {
if (getEntriesBytes() != null) {
ByteArrayInputStream byteIn =
new ByteArrayInputStream(getEntriesBytes());
ObjectInputStream objIn = new ObjectInputStream(byteIn);
mEntries = (Properties)objIn.readObject();
}
// If no entries in database, set properties to a new, empty collection
else {
mEntries = new Properties();
}
}
catch (ClassNotFoundException cnfe) {
System.out.println("Properties class not found during de-serialization");
}
}
//--------------------------------------------------
// Entity bean methods
//--------------------------------------------------
// After the container reloads our byte array from passivated state,
// convert it back into a Properties object.
public void ejbActivate() {
try {
transferToProps();
System.out.println("ProfileBean activated.");
}
catch (IOException ioe) {
System.out.println("Failed to convert entries during activation.");
ioe.printStackTrace();
}
}
// Before passivation occurs, copy the entries list from the Properties
// member into the byte array.
public void ejbPassivate() {
try {
transferToBytes();
System.out.println("ProfileBean being passivated.");
}
catch (IOException ioe) {
System.out.println("Failed to convert entries during activation.");
ioe.printStackTrace();
}
}
// Load bean from persistent store. Since the profile entries are stored in
// a non-primitive object (Properties), they are stored in the database as a
// raw byte array (BLOB). In this load method, we convert the serialized
// bytes loaded by the container into the original Properties object.
public void ejbLoad() {
try {
transferToProps();
}
catch (IOException e) {
System.out.println("Failed to load ProfileBean: ");
e.printStackTrace();
throw new EJBException("ejbLoad failed: ", e);
}
System.out.println("ProfileBean load finished.");
}
// Store bean to persistent store. We store our Properties object in the
// database as a serialized byte array. Here, we serialize the Properties
// object so that the container can store it.
public void ejbStore() {
try {
transferToBytes();
}
catch (IOException e) {
System.out.println("Failed to store ProfileBean: ");
e.printStackTrace();
throw new EJBException("ejbStore failed: ", e);
}
System.out.println("ProfileBean store finished.");
}
// Nothing to do on a remove.
public void ejbRemove() {
System.out.println("ProfileBean removed.");
}
// Get context from container.
public void setEntityContext(EntityContext context) {
System.out.println("ProfileBean context set.");
mContext = context;
}
// Container is removing our context.
public void unsetEntityContext() {
System.out.println("ProfileBean context unset.");
mContext = null;
}
// Create method (corresponds to each create() method on the
// home interface, ProfileHome). Here, we initialize our persistent
// properties to sensible starting values.
public String ejbCreate() throws CreateException {
System.out.println("Nameless ProfileBean created.");
setName(" ");
clearEntries();
return null;
}
// Post-creation notification. Nothing to do here, but we need
// to provide an implementation.
public void ejbPostCreate() {
System.out.println("ProfileBean post-create called.");
}
// Create method with name of profile owner.
public String ejbCreate(String name)
throws CreateException, NoSuchPersonException {
setName(name);
clearEntries();
System.out.println("ProfileBean created for " + name + ".");
return null;
}
// Post-creation notification. Nothing to do here, what we need
// to provide an implementation.
public void ejbPostCreate(String name) {
System.out.println("ProfileBean post-create called.");
}
//--------------------------------------------------
// Business methods
//--------------------------------------------------
public String getEntry(String key) {
System.out.println("getEntry(): principle = " +
mContext.getCallerPrincipal().getName());
return mEntries.getProperty(key);
}
public void setEntry(String key, String value) {
mEntries.put(key, value);
}
// EJB 2.x: Accessors for the relationship with the corresponding
// Person bean.
// Get local person for this profile
abstract public PersonLocal getPersonLocal();
abstract public void setPersonLocal(PersonLocal person);
// Utility method used to clear all entries and initialize
// data members appropriately
private void clearEntries() {
// Initialize our profile properties to an empty set, and
// transfer the empty collection to the byte array
this.mEntries = new Properties();
try {
transferToBytes();
}
catch (IOException ioe) {
System.out.println("Failed to initialize binary entries: "
+ ioe.getMessage());
}
}
}
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