Which variables are initialized by default value?
Unlike local variables, class variables and instance variables are given default values. Numeric types are automatically initialized to zero, and String variables are initialized to empty strings.
Which variables are not initialize By default values in Java?
The local variables do not have any default values in Java. This means that they can be declared and assigned a value before the variables are used for the first time, otherwise, the compiler throws an error.
What is default value of int variable?
Default Values
| Data Type | Default Value (for fields) |
|---|---|
| int | 0 |
| long | 0L |
| float | 0.0f |
| double | 0.0d |
Is it good practice to initialize variables?
3 Answers. The basic rule of thumb is to initialize a resource when you need it, and no later. Ideally, you should only need to check for initialization infrequently (preferably no more than once, or never). It’s often possible to write code where no null checks are ever made, because none are needed.
What is the default value of local variable?
The default value of the local variable is NULL in JAVA, no primitive values or object references.
When to use Default initialization of instance variables in Java?
When you declare a variable without assigning it an explicit value, the Java compiler will assign a default value. Let’s consider the following example: NOTE: This default initialization applies for instance variables, not for method variables. For variables in method, we have to initialize them explicitly. So remember these rules:
When do you assign a default value to a Java variable?
When you declare a variable without assigning it an explicit value, the Java compiler will assign a default value. Let’s consider the following example: NOTE: This default initialization applies for instance variables, not for method variables. For variables in method, we have to initialize them explicitly.
What is the default value of an integer?
Integer numbers have default value: 0. for int type: 0. for byte type: (byte) 0. for short type: (short) 0. for long type: 0L. Floating point numbers have default value: 0.0. for float type: 0.0f.
When does an array have a default value?
When the size of an array is initialized, then its components will have default values specified by the rules above. For example: NOTE: The default initialization of array components is the same, regardless of the array itself is member variable or local variable.