Basically, inlining is a way to optimize compiled source code at runtime by replacing the invocations of the most often executed methods with its bodies. Although there’s compilation involved, it’s not performed by the traditional javac compiler, but by the JVM itself.

Boost your Android productivity — Use Compound ViewGroups If not, then good you already know what it is. A Compound ViewGroup is nothing but a reusable group of views bundled together inside an Android ViewGroup (such as LinearLayout, RelativeLayout etc.), which can be treated as a single thing.

In the case of lambdas, the actual function being called is a member operator() that is implicitly defined as inline in an anonymous class created by the compiler for the lambda. Calls of the lambda are translated to direct calls to its operator() and can therefore be inlined.

Abstract Classes and Methods Abstract class: is a restricted class that cannot be used to create objects (to access it, it must be inherited from another class). Abstract method: can only be used in an abstract class, and it does not have a body. The body is provided by the subclass (inherited from).

The main() method is static so that JVM can invoke it without instantiating the class. This also saves the unnecessary wastage of memory which would have been used by the object declared only for calling the main() method by the JVM. Void: It is a keyword and used to specify that a method doesn’t return anything.

The String[] args parameter is an array of Strings passed as parameters when you are running your application through command line in the OS. String[] args means an array of sequence of characters (Strings) that are passed to the “main” function. This happens when a program is executed.

Yes, we can execute a java program without a main method by using a static block. Static block in Java is a group of statements that gets executed only once when the class is loaded into the memory by Java ClassLoader, It is also known as a static initialization block.

The answer is no; there can only one “main” method – where “main” means an entry point you can “run”. You can code overloaded versions as in your example, but they can’t be “run”. There can be more than one main method in a single program. But JVM will always calls String[] argument main() method.

Main is not a keyword in Java. The language specification also mandates that there should be a method named “main”, which should be public and static and accept an array of strings as parameter with the return type as void.

A JAR file can contain one or more main classes. Each main class is the entry point of an application. So, theoretically, a JAR file can contain more than one application, but it has to contain at least one main class to be able to run. A JAR file can have one entry point set in its manifest file.

Technically a jar file can contain more than one main class. When java executes a jar file, it looks in the META-INF/MANIFEST. MF file inside the jar to find the entrypoint. There is no direct command to get this information, but you can unpack the jar (it’s just a zip file) and look into the manifest yourself.

Java main() method is always static, so that compiler can call it without the creation of an object or before the creation of an object of the class. So, the compiler needs to call the main() method. If the main() is allowed to be non-static, then while calling the main() method JVM has to instantiate its class.

If you are getting this error in your Gradle project, you can solve this by putting the following entries in your build. gradle file:

1. plugins {
2. id ‘java’
3. }
4. jar {
5. manifest {
6. attributes(
7. ‘Main-Class’: ‘com. javatpoint. AppMain’
8. )

The Main attribute is necessary to tell java which class it should use as the application’s entry point. Inside the jar file, the MANIFEST. You get this “no main manifest attribute” error when this line is missing from the MANIFEST. When you run a self-executable jar, java will look for the Main-Class in MANIFEST.