Array Data Structure Java Example

The following example shows how to abstract array data structure functionality and make it easier to design a program. The user life is made easier and the user doesn’t even need to know what kind of data structure the ArrayDataStructure class is using to store the data.

Array data structure with high-level methods

package com.sneppets.dsalgo;

public class ArrayDataStructure {
	
	//reference to array arr
	private long[] arr; 
	
	//number of elements in the array
	private int n;
	
	//constructor
	public ArrayDataStructure (int arrSize){
		
		//create array
		arr = new long[arrSize];
		
		//no elements yet 
		n = 0;
	}
	
	//find element
	public boolean find (long elementKey){
		
		int i;
		
		for (i=0; i<n; i++){			
			if (arr[i] == elementKey)
				break;			
		}
		
		if (i == n){			
			return false;			
		}
		
		else{			
			return true;			
		}	
	}
	
	//insert element into array
	public void insert(long element){
		
		//insert element
		arr[n] = element;
		
		//increment size
		n++;
	}
	
	public boolean delete(long element){
		
		int i;
		
		for (i=0; i<n; i++){			
			if(element == arr[i])
				break;			
		}
		
		if (i == n){			
			return false;			
		}
		else {		
			//move higher ones down
			for(int j=i; j<n; j++){
				arr[j] = arr[j+1];
			}
			//decrement size
			n--;
			
			return true;
		}
		
	}
	
	//display array contents
	public void display(){
		
		for(int i=0; i<n; i++){
			
			System.out.println(arr[i]+ " ");
			
		}
			
	}

}

ArrayDataStructureTest.java

package com.sneppets.dsalgo;

public class ArrayDataStructureTest {
	
	public static void main (String[] args){
		
		//array size
		int arrSize = 10;
		
		//reference to array data structure
		ArrayDataStructure arrayDS;
		
		//create the array
		arrayDS = new ArrayDataStructure(arrSize);
		
		//insert 5 elements
		arrayDS.insert(11);
		arrayDS.insert(33);
		arrayDS.insert(55);
		arrayDS.insert(22);
		arrayDS.insert(44);
		
		//display array elements
		arrayDS.display();
		
		//search for element 77
		int element = 77;
		if(arrayDS.find(element)){			
			System.out.println("Found element "+ element);			
		}
		else{			
			System.out.println("Could not find element "+ element);			
		}
		
		//delete 2 elements
		arrayDS.delete(33);
		arrayDS.delete(55);
		
		//display again
		arrayDS.display();		
	}

}

Output:

11 
33 
55 
22 
44 
Could not find element 77
11 
22 
44