persistence

Simple question about property lists within an iphone app. I know you can read data in from a plist, but is there a way to write user-inputted data to a plist? If so, how? It's easy to find tutorials on reading information from plists, but I'm having trouble finding resources on writing to plists. This is how I write data items to a plist: [myPlistFile setInteger: myInt forKey: @"someKey"]; Of course, you can change setInteger with setBool, etc for different types. Hope this helps! -- Edit: If your .plist was a member of an important class or similar... Header of myClass: NSUserDefaults*

Prevayler guarantees that all the writes ( through its transactions) are synchronized. But what about reads? Is it right that dirty reads are possible if no explicit synchronizing is used (in user code)? Are they possible if a business object is read as: // get the 3rd account Accont account = (Bank)prevayler.prevalentSystem().getAccounts().get(2); ? If so what synchronizing strategies are good for a user code? (Consider a business object A contains a collection of business objects Bs), using a synchronized collection (of Bs inside of A), for example from java.util.concurrent package?

HI, I have an object which has a piece of URL-Information associated with it. Currently I save this URL in a simple String property, but java.net.URL would provide me with additional goodies such as detection of malformed URLs etc. On the other hand I would consider it very ugly, if JPA simply created a LOB for the URL-Object. Does anyone know how a property of the type java.net.URL will be persisted to the database by compliant JPA providers? As per the JPA spec: The persistent fields or properties of an entity maybe of the following types: Java primitive types; java.lang.String; other Java

Related to: Is there a way to obtain the bytecode for a class at runtime? I'm adding durability to Clojure, and I'm finally at the point where I'm ready to add functions. In Clojure, functions are byte compiled into classes with invoke methods (among others). In this way, functions are first class. To make these durable, I need to serialize and deserialize these classes. How do I get the bytecode for the class without having access to the .class file? Please correct me if I'm mistaken, but using an agent requires spawning a separate VM with the agent connecting to the first VM. I need to do it

Working on some legacy hibernate code. How do I do the following with hbm.xml(hibernate mapping file) instead of with annotations? @Table(name="users", uniqueConstraints = { @UniqueConstraint(columnNames={"username", "client"}), @UniqueConstraint(columnNames={"email", "client"}) }) public class User implements Serializable { private static final long serialVersionUID = 1L; @Id private int id; private String username; private String email; private Client client; } Use the properties tag: ... <properties name="uk1" unique="true"> <property name="username" .../> <many-to-one name="client" .../> <

I have an app that fetches data from the internet and uses CoreData to store them in the device, for a smoother experience. Because I use Core Data, every time my schema changes, the app crashes when I try to run it with the previous data stored on the device. What is the fastest way to detect this change and wipe all the data from the device, since I don't mind redownloading them all. It beats crashing and remapping the schema to the new one (in my case). I see that this check is performed in the getter: - (NSPersistentStoreCoordinator *)persistentStoreCoordinator so I only need to know the