ObjectInputStream registerValidation(ObjectInputValidation, int) in Java

registerValidation(ObjectInputValidation, int): This method is available in the java.io.ObjectInputStream class of Java.

Syntax:

void java.io.ObjectInputStream.registerValidation(ObjectInputValidation obj, int prio) throws NotActiveException, InvalidObjectException

This method takes two arguments. This method registers an object to be validated before the graph is returned. While similar to resolving objects these validations are called after the entire graph has been reconstituted.

Typically, a readObject method will register the object with the stream so that when all of the objects are restored a final set of validations can be performed.

Parameters: Two parameters are required for this method.

obj: the object to receive the validation callback.

prio: controls the order of callbacks; zero is a good default. Use higher numbers to be called back earlier, and lower numbers for later callbacks. Within a priority, callbacks are processed in a particular order.

Returns: NA

Throws:

1. NotActiveException - The stream is not currently reading objects so it is invalid to register a callback.

2. InvalidObjectException - The validation object is null.

Approach

Java

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;

public class ObjectInputStreamregisterValidation {
    public static void main(String[] args) throws IOException {

        InputStream in = new FileInputStream("D:\\hello.txt");
        ObjectInputStream objectInputStream =
                                    new ObjectInputStream(in);

        objectInputStream.registerValidation(null, 100100);
        System.out.println("Successfully registered validation");
        objectInputStream.close();

    }
}

Output:

Exception in thread "main" java.io.NotActiveException: stream inactive
	at java.base/java.io.ObjectInputStream.registerValidation(ObjectInputStream.java:733)
	at com.ObjectInputStream.ObjectInputStreamregisterValidation.main(ObjectInputStreamregisterValidation.java:14)

Some more methods of ObjectInputStream

available(): This method returns the number of bytes that can be read without blocking.

close(): This method closes the input stream. Must be called to release any resources associated with the stream.

defaultReadObject(): This method read the non-static and non-transient fields of the current class from this stream.

getObjectInputFilter(): This method returns the serialization filter for this stream.

read(): This method reads a byte of data.

read(byte[], int, int): This method reads into an array of bytes.

readBoolean(): This method reads in a boolean.

readByte(): This method reads an 8-bit byte.

readChar(): This method reads a 16-bit char.

readDouble(): This method reads a 64-bit double.

readFields(): This method reads the persistent fields from the stream and makes them available by name.

readFloat(): This method reads a 32-bit float.

readFully(byte[]): This method reads bytes, blocking until all bytes are read.

readFully(byte[], int, int): This method reads bytes, blocking until all bytes are read.

readInt(): This method reads a 32-bit int.

readLong(): This method reads 64-bit long.

readObject(): This method read an object from the ObjectInputStream.

readShort(): This method reads a 16-bit short.

readUnshared(): This method reads an "unshared" object from the ObjectInputStream.

readUnsignedByte(): This method reads an unsigned 8-bit byte.

readUnsignedShort(): This method reads an unsigned 16-bit short.

readUTF(): This method reads a String in modified UTF-8 format.

setObjectInputFilter(ObjectInputFilter): This method set the serialization filter for the stream.

skipBytes(int): This method skips bytes.