How to check the object is an iterable or not?

Using Class.isAssignableFrom method, we can check whether given object is an iterable or not.

 

Signature

public native boolean isAssignableFrom(Class<?> cls)

'isAssignableFrom' method return true, if the class or interface represented by this Class object is either the same as, or is a superclass or superinterface of, the class or interface represented by the specified Class parameter, else false.

 

Example

public static boolean isIterable(final Class<?> clazz) {
    return clazz != null && (Iterable.class.isAssignableFrom(clazz));
}

 

Above snippet return true, if the given type an iterable, else false.

 

Find the below working application.

 

IterableCheckDemo.java

package com.sample.app.collections;

import java.util.Arrays;
import java.util.HashMap;

public class IterableCheckDemo {
	
	public static boolean isIterable(final Class<?> clazz) {
        return clazz != null && (Iterable.class.isAssignableFrom(clazz));
    }
	
	public static void main(String[] args) {
		final Object list = Arrays.asList(2, 3, 5, 7);
		final Object map = new HashMap<>();
		
		System.out.println("Is list iterable : " + isIterable(list.getClass()));
		System.out.println("Is map iterable : " + isIterable(map.getClass()));
	}

}

 

Output

Is list iterable ? true
Is map iterable ? false

 

  

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