Hi all,
Need a little help in using the persistence of appengine. First of all
the code:
Feed.java
=========================
@PersistenceCapable(identityType = IdentityType.APPLICATION)
public class Feed {
@Persistent
final String title;
@Persistent
final String link;
@Persistent
final String description;
@Persistent
final Date pubDate;
// @PrimaryKey
// @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY)
// private Key key;
@Persistent (valueStrategy = IdGeneratorStrategy.IDENTITY)
@GeneratedValue(strategy=GenerationType.SEQUENCE)
@PrimaryKey
private Long id;
public Feed(String title, String link, String description,Date
pubDate) {
this.title = title;
this.link = link;
this.description = description;
this.pubDate = pubDate;
}
public String getTitle() {
return title;
}
public String getLink() {
return link;
}
public String getDescription() {
int junkIndex = description.indexOf("More horoscopes");
return description.substring(0, junkIndex-1);
}
public Date getPubDate() {
return pubDate;
}
}
=======================================
Code for saving the data:-
=======================================
private static List<Feed> feeds;
PersistenceManager pm = PMF.get().getPersistenceManager();
try {
pm.makePersistentAll(feeds);
} finally {
pm.close();
}
=========================================
Code for retrieving data:-
========================================
PersistenceManager pm = PMF.get().getPersistenceManager();
String query = "select from " + Feed.class.getName() ;
List<Feed> feeds = (List<Feed>) pm.newQuery(query).execute();
for(int i=0;i<feeds.size();i++) {
Feed feed = feeds.get(i);
if (feed.getTitle().contains("test")) return feed;
}
return null;
===================================
The problem:-
===================================
While saving I can see that proper title,description etc are getting
stored in the Feed class. But while retreiving, the values are coming
as NULL.
So I am getting null pointer at
if (feed.getTitle().contains("test"))
Could anybody please help me with this?
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