What is the role of java Optional

Explanation

1. Optional is not a function interface, but is to prevent null pointer exceptions.

2. Optional can be regarded as a container that wraps objects (can be null or non-null). As defined as a method, the returned object may be empty or non-null. You can consider using Optional for packaging, which is also the recommended method in Java8.

Example

Optional<String> optional = Optional.of("bam");
 
optional.isPresent();           // true
optional.get();                 // "bam"
optional.orElse("fallback");    // "bam"
 
optional.ifPresent((s) -> System.out.println(s.charAt(0)));     // "b"

What are the basic data types of java

The basic data types of Java are divided into:

1. Integer type , a data type used to represent integers.

2. Floating point type, a data type used to represent decimals.

3. Character type. The keyword of character type is "char".

4. Boolean type is the basic data type that represents logical values.

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