Technology Questions

Java Collections Framework provides a well designed set of interfaces and classes that support operations on a collections of objects. The most basic interfaces that reside in the Java Collections Framework are:

Collection, which represents a group of objects known as its elements.

Set, which is a collection that cannot contain duplicate elements.

List, which is an ordered collection and can contain duplicate elements.

Map, which is an object that maps keys to values and cannot contain duplicate keys.

A call to onStop method happens when an activity is no longer visible to the user, either because another activity has taken over or if in front of that activity.

Executing two or more blocks (threads) of a program at a time is called MultiThreading.

These objects provide two levels of scope:

Application State

Data stored in the application object can be shared by all the sessions of the application.

Application object stores data in the key value pair.

By default the maximum size is 2MB. and we can change the following
setup at php.iniupload_max_filesize = 2M

AlertDialog : An alert dialog box supports 0 to 3 buttons and a list of selectable elements, including check boxes and radio buttons. Among the other dialog boxes, the most suggested dialog box is the alert dialog box.

ProgressDialog: This dialog box displays a progress wheel or a progress bar. It is an extension of AlertDialog and supports adding buttons.

DatePickerDialog: This dialog box is used for selecting a date by the user.

TimePickerDialog: This dialog box is used for selecting time by the user.

The mapreduce framework contains most of the key architecture principles of cloud computing such as:

- Scale: The framework is able to expand itself in direct proportion to the number of machines available.

- Reliable: The framework is able to compensate for a lost node and restart the task on a different node.

- Affordable: A user can start small and over time can add more hardware.

- localStorage object stores the data without an expiry date while sessionStorage object stores the data only for one session. 

- With localStorage object, data will not be deleted when the browser window is closed while the data is deleted when the browser window closes with sessionStorage objects.