How do I serialize an object to a file?
To serialize an object means to convert its state to a byte stream so that the byte stream can be reverted back into a copy of the object. A Java object is serializable if its class or any of its superclasses implements either the java.io.Serializable interface or its subinterface, java.io.Externalizable. Deserialization is the process of converting the serialized form of an object back into a copy of the object. Show For example, the java.awt.Button class implements the Serializable interface, so you can serialize a java.awt.Button object and store that serialized state in a file. Later, you can read back the serialized state and deserialize into a java.awt.Button object. The Java platform specifies a default way by which serializable objects are serialized. A (Java) class can override this default serialization and define its own way of serializing objects of that class. The Object Serialization Specification describes object serialization in detail. When an object is serialized, information that identifies its class is recorded in the serialized stream. However, the class's definition ("class file") itself is not recorded. It is the responsibility of the system that is deserializing the object to determine how to locate and load the necessary class files. For example, a Java application might include in its classpath a JAR file that contains the class files of the serialized object(s) or load the class definitions by using information stored in the directory, as explained later in this lesson. Binding a Serializable ObjectYou can store a serializable object in the directory if the underlying service provider supports that action, as does Oracle's LDAP service provider. The following example invokes // Create the object to be bound Button b = new Button("Push me"); // Perform the bind ctx.bind("cn=Button", b); You can then read the object back using
// Check that it is bound Button b2 = (Button)ctx.lookup("cn=Button"); System.out.println(b2); Running # java SerObj java.awt.Button[button0,0,0,0x0,invalid,label=Push me] Specifying a CodebaseNote: The procedures described here are for binding a serializable object in a directory service that follows the schema defined in RFC 2713. These procedures might not be generally applicable to other naming and directory services that support binding a serializable object with a specified codebase. When a serialized object is bound in the directory as shown in the previous example, applications that read the serialized object from the directory must have access to the class definitions necessary to deserialize the object. Alternatively, you can record a codebase with the serialized object in the directory, either when you bind the object or subsequently by adding an attribute by using The following example resembles the one for binding a java.awt.Button. It differs in that it uses a user-defined Serializable class, String codebase = ...; // Create the object to be bound Flower f = new Flower("rose", "pink"); // Perform the bind and specify the codebase ctx.bind("cn=Flower", f, new BasicAttributes("javaCodebase", codebase)); When you run # java SerObjWithCodebase http://web1/example/classes/ pink rose Afterward, you may remove Flower.class from your classpath and run any program that looks up or lists this object without directly referencing the Flower class. If your program references Flower directly, then you must make its class file available for compilation and execution. How do you serialize an object?To serialize an object. Create the object and set its public fields and properties.. Construct a XmlSerializer using the type of the object. ... . Call the Serialize method to generate either an XML stream or a file representation of the object's public properties and fields.. Can object be written to a file in Java?Java object Serialization is an API provided by Java Library stack as a means to serialize Java objects. Serialization is a process to convert objects into a writable byte stream. Once converted into a byte-stream, these objects can be written to a file.
Which method is used to serialize an object to open?For serializing the object, we call the writeObject() method of ObjectOutputStream class, and for deserialization we call the readObject() method of ObjectInputStream class.
What happens when you serialize an object?Serialization is the process of converting an object into a stream of bytes to store the object or transmit it to memory, a database, or a file. Its main purpose is to save the state of an object in order to be able to recreate it when needed. The reverse process is called deserialization.
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