How to deep copy in java

What is shallow copy and deep copy in Java with example?

In shallow copy, only fields of primitive data type are copied while the objects references are not copied. Deep copy involves the copy of primitive data type as well as objet references.

How can you achieve the deep cloning of an object?

Deep Cloning

We can do it by implementing a Cloneable interface and overriding the clone() method in every reference type we have in our object hierarchy. Then, we call super. clone() and these clone() methods in our object’s clone method.

How do you copy an object in Java 8?

Creating a copy using clone() method

clone() to obtain the cloned object reference. The class must also implement java. lang. Cloneable interface whose object clone we want to create otherwise it will throw CloneNotSupportedException when clone method is called on that class’s object.13 мая 2019 г.

How do you make a deep copy in Java?

The steps for making a deep copy using serialization are:

  1. Ensure that all classes in the object’s graph are serializable.
  2. Create input and output streams.
  3. Use the input and output streams to create object input and object output streams.
  4. Pass the object that you want to copy to the object output stream.

Is Java clone a deep copy?

Deep copy of an object will have exact copy of all the fields of original object just like shallow copy. But in additional, if original object has any references to other objects as fields, then copy of those objects are also created by calling clone() method on them.

See also:  How to convert an array to an arraylist in java

How do you create a deep copy?

To create deep copy we need to override the clone method of Object class. A deep copy is preferred if the object’s class variables have references to other objects as fields.

Which class contains clone method?

The clone() method of Object class is used to clone an object. The java. lang. Cloneable interface must be implemented by the class whose object clone we want to create.

What is clone () in Java?

JavaObject Oriented ProgrammingProgramming. The object cloning is a way to create an exact copy of an object. For this purpose, the clone() method of an object class is used to clone an object. The Cloneable interface must be implemented by a class whose object clone to create.

How does Clone method work?

clone() method acts like a copy constructor. It creates and returns a copy of the object. Since the Object class has the clone method (protected) you cannot use it in all your classes. The class which you want to be cloned should implement clone method and overwrite it.

What is shallow and deep copy?

A shallow copy constructs a new compound object and then (to the extent possible) inserts references into it to the objects found in the original. A deep copy constructs a new compound object and then, recursively, inserts copies into it of the objects found in the original.

Why is Java clone broken?

Cloneable and Object. clone() are “broken” in the sense that they have design flaws and are difficult to use correctly. However, clone() is still the best way to copy arrays, and cloning has some limited usefulness to make copies of instances of classes that are carefully implemented.

See also:  How to use arrays.Sort in java

How many types of cloning are there in Java?

Cloning in Java can be grouped into two categories: Shallow Cloning. Deep Cloning.

How do you clone an ArrayList?

ArrayList cloned = new ArrayList(collection c); where c is the collection containing elements to be added to this list.


  1. Create a list to be cloned.
  2. Create an empty list using the ArrayList constructor.
  3. Append the original list to the empty list using the addAll() method.

How do you copy an ArrayList?

The clone() method of the java. util. ArrayList class returns a shallow copy of this ArrayList instance (i.e the elements themselves are not copied). Using this method, you can copy the contents of one array list to other.

Leave a Comment

Your email address will not be published. Required fields are marked *