The document provides an overview of constructors in Java, detailing their significance in creating and managing objects effectively. It explains the types of constructors, including parameterized and non-parameterized, along with their respective uses and advantages. Additionally, it highlights rules governing constructors, such as naming conventions and the absence of return types.

1. Constructor in JAVA
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2. Content
 Why we need constructor?
Example
 Use of constructor.
 Type of constructor.
Example
 Rules for constructor.
 Advantages of constructor.
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3. Why we need constructor?
 Suppose we create a class Student with some attributes.
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4. Why we need constructor?
 So now if we want to create object of this class and assign values to its
variables we have to use instance of object.
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 If we use instance of class
object to assign the value to
variables then it will increase
the LOC.
 We have assign values to
each variable separately
and this is not possible with
the classes having more
variables.
 This is where Constructor
comes in play.

5. Use of constructor.
 Constructor help us to assign values to variables at the time of object
creation.
 Constructor accept values as an attributes of object at the time of
creation.
 Every time we create object, default constructor has been called.
 Constructor can be use to display message.
Simple Definition
 Constructor is a method which name is same as class name and it get
executed at the time of object creation.
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6. Type of constructor.
 There are 2 types of constructor.
 Parameterized
 Non-Parameterized
 Parameterized
 Parameterized constructors are the one which helps up to accept values at the
time of object creation.
 Non-Parameterized
 Non-Parameterized don't accept values at the time of object creation, but they
can be used to display message.
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7. Parameterized Constructor
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8. Parameterized Constructor
 In above example when we pass values in Student class
object compiler called the constructor, which accepts
values and assign those values to global variables.
 Output :
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9. Non-Parameterized Constructor
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10. Non-Parameterized Constructor
 Non-Parameterized Constructor can be use to display
the message.
 Output :
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11. Rules for constructor.
 Constructor doesn't have any return type.
 Name of constructor is same as class’s name.
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12. Advantages of constructor.
We don’t have to use object instance for
assigning the values to class variables.
It helps to reduce LOC(Line of Code).
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