Java is one of the most popular programming languages used in Win applications, Web Applications to Mobile, Network, consumer electronic goods, set-top box devices, etc. It is the most popular development platform. Learning Java and implementing it in the form of an assignment is tough and here is where a student seeks programming assignment help.
Students nowadays easily find many online assignment help services where they get their assignment done and just submit it to their professors.
It is not easy to be an assignment writer. It takes a lot of practice. But somewhere it needs to be started. Here are few points by learned people for Java programmers and bug-free programming tips.
• Make sure to return an Empty collection rather than Null elements in the case where a program is returning a collection which does not have any value. This will save a lot of “if else” testing on Null Elements.
• When two Strings are connected using “+” operator in a “for” loop, then it creates a new String Object, all the time. This leads to wastage of memory while increasing performance time. Also, when instantiating a String Object, avoid constructors and instantiation will occur directly.
• Object creation is one of the most expensive operations when it comes to the terms of Memory Utilization in Java. Hence, it is advised that Objects must only be created or initialized when necessary.
• It is often difficult for developers to take a decision if they should opt for Array type data structure of ArrayList type. However, both of them have their strengths and weaknesses. The choice really depends on the requirements. Arrays have their size, but ArrayLists comes in variable sizes. Due to the fixed size of Array, the memory gets allocated at the time of declaration of Array type variable. Due to this Arrays are very fast. But if we do not know the size of the data, then ArrayList with More data will give rise to ArrayOutOfBoundException, and fewer data will lead to the wastage of storage space. It is pretty easy to Add or Remove elements from ArrayList than Array. The array can be multi-dimensional, but ArrayList can only be in one dimension.
• Exporting a table to PDF is a common requirement in Java programs. Use itextpdf, it becomes very easy to export PDF.
• It is very simple to sending email from Java. Just install Java Mail Jar and set its path in the program’s classpath.
• There are many applications that require a very precise time measurement. Fulfilling this purpose, Java provides static methods in System class:
currentTimeMillis(): Returns current time in MilliSeconds since Epoch Time, in Long.
nanoTime(): Returns the current value of the most precise available system timer, in nanoseconds, in long. nanoTime() is meant for measuring relative time interval instead of providing absolute timing.
• An image can be rescaled using affine transform. Image Buffer of an input image is created first, and then a scaled image is rendered.
• Mouse events can be captured by using MouseMotionListner Interface. When the mouse is entered in a specific region MouseMoved Event is triggered, and motion coordinates will be captured.
• FileOutputStream is used for writing streams of raw bytes such as image data. For writing streams of characters, try using FileWriter.
• GUI can be created with the help of Java Swing. Java has something called Javax which contains “swing”. The GUI uses swing beginning with extending JFrame. Boxes are added so they can contain GUI components like Button, Radio Button, Textbox, etc. These boxes are set on top of Container.
• Java gives Runtime class to execute Shell Commands. Exception handling is really important since these are external commands.
Few rules to fix bugs:
• No need to depend on initialization
There are many ways of allocation of an object without calling a constructor.
It is better to declare all the variables as private. The GET and SET method are used to access the object outside the class. Write a new private Boolean variable for each object and initialize it. Also, write a non-constructor class that will ensure that each object is initialized before calling anywhere in the code.
• Your Classes, Method, and Variables must be secured
When writing your code, make some classes, methods, and variables as private and some as public. Private classes cannot be accessed easily which makes them a secure point of the code, whereas in the public methods, variables can be easily accessed and they become a point to be attacked. This is to be made when it is the only option. So, make them with limited scope.
• Scope must be predefined always
It is better to always predefine the scope of your code. Many classes exist that are not closed on their own. It leaves a loophole for the hackers where he uses a single loophole to insert his/her own class to use the sensitive information from your code. By default, JVM is not closed. This allows you to close your classes within the package.
• Do not use inner classes
Generally, what the developers do is that they use the inner classes whenever they’re needed in other classes within the same package. Since it is already advised to redefine the scope of each and every class that you create in the code, the inner classes are usually accessible to all the other classes in the same package.
• No non-cloneable classes
Java tends to clone its own classes whenever required. Hackers take advantage of this feature. He can easily use the java.lang.Cloneable to duplicate the instances of the code and steal necessary information.
About Author: Thomas Lewis comes from the University of Dundee who teaches students java programming. He has been in this industry for many years working as a guest lecturer in many educational institutes. He reaches out to students who need programming assignment help. He is also associated with MyAssignmenthelp.com.