arrays notice how short and simple main(is the details that had to be handled by main(in lowarray java are now handled by higharray class methods in the higharray classthe find(method looks through the array for the item whose key value was passed to it as an argument it returns true or falsedepending on whether it finds the item the insert(method places new data item in the next available space in the array field called nelems keeps track of the number of array cells that are actually filled with data items the main(method no longer needs to worry about how many items are in the array the delete(method searches for the element whose key value was passed to it as an argument andwhen it finds that elementshifts all the elements in higher index cells down one cellthus writing over the deleted valueit then decrements nelems we've also included display(methodwhich displays all the values stored in the array the user' life made easier in lowarray java (listing )the code in main(to search for an item required eight linesin higharray javait requires only one the class userthe higharrayapp classneed not worry about index numbers or any other array details amazinglythe class user doesn' even need to know what kind of data structure the higharray class is using to store the data the structure is hidden behind the interface in factin the next sectionwe'll see the same interface used with somewhat different data structure abstraction the process of separating the how from the what--how an operation is performed inside classas opposed to what' visible to the class user--is called abstraction abstraction is an important aspect of software engineering by abstracting class functionalitywe make it easier to design program because we don' need to think about implementation details at too early stage in the design process the ordered workshop applet imagine an array in which the data items are arranged in order of ascending key values--that iswith the smallest value at index and each cell holding value larger than the cell below such an array is called an ordered array when we insert an item into this arraythe correct location must be found for the insertionjust above smaller value and just below larger one then all the larger values must be moved up to make room