Servlet Overview Earlier Common Gateway Interface (CGI) server-side scripts used to generate dynamic content. Disadvantages of CGI Platform dependence Lack of scalability Always a new process should be created to serve a request. i.e. f there are N simultaneous requests to the same CGI program, the code for the CGI program is loaded into memory N times….
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Java SE 8 features
Java SE 8 Features Some of the important Java se 8 features are Please click on each link for detailed explanation lambda expressions functional interface foreach method in java.lang.iterable Default methods and Static methods Method References Remaining features will be updated soon ………
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How to create immutable class in Java? Immutable class is a class which once created, its contents cannot be modified. Immutable objects are the objects whose state cannot be modified once it is created. Best example to explain the difference between mutable and immutable is String and StringBuffer. String is immutable class (Refer String is…
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String is immutable or final in Java? One of the Interviewers favourite question, How String plays an important role in every program, similarly in every interview questions on String will be there 🙂 😉 . Let’s check the reasons behind why String is immutable of final. Security: String is used in many places like in…
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Almost in every program, String is being used. When we create a string, it is stored in String pool, as name indicates it is a pool of Strings stored in Java Heap Memory. We can create String in 2 ways By using new operator, String v1 = new String(“Test”); Directly assign the value using Double…
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Generics Java Generics features were introduced from Java Se 5 onwards. Before Java 5, we can store any type of objects in collection i.e. non generic. With inclusion of Generics we need to store only specific type of objects only. Let’s look at the benefits of generics Compile time checking: Generics allows you to check…
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Custom Annotation Similar to interface we can define Custom Annotations or user defined annotations simply by adding @interface in the declaration. For example: @interface CustomAnnotation{} Here, CustomAnnotationis the custom annotation name. While writing the custom annotations few points has to be considered. Method should not have any throws clauses, Similar to interface only declarations available…
Continue readingJava se 8 Repeating Annotations
Repeating Annotations ( Java SE 8) In some cases we need to use Repeated Annotations as per the requirement @Retention(RetentionPolicy.RUNTIME) @interface CustomAnnotation { String city() ; int pin() default 123; } @CustomAnnotation(city = “Vijayawda”) @CustomAnnotation(city = “Chennai”) public static void testAnnotation() { System.out.println(“Custom annotation test”); } If you use repeated Annotations like this compiler will…
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Annotations in java Annotations in java, a form of metadata, provide data about a program.Java annotations do not directly affect the execution of your code. The main purposes of Java Annotations are Annotations provides information to compiler for detecting errors or suppress warnings etc.(Compiler Instructions) Annotations are used at build time and deployment time processing…
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Java 5 Features Some of the important Java 5 features are Enumeration or enum Autoboxing Unboxing Static Import Var args Variable Argument Annotations Generics Click on the above links to view the detailed explanation.
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