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Small Changes to Java 7 via Project Coin and Why They are Useful

Did you know how new features were added into Java 7? The following are functionalities that can be considered. Source: [1] Project Coin  is all about the changes in the range from syntactic sugar to new language feature. This is what we're talking about today. Since Java 7 is the first version developed in an open source manner, there is an amount of actions that must be performed for any changes as follows: Update the Java Language Specification (JSL) Implement a prototype in the source compiler Add library support essential for the change Write tests and examples Update document Etc, ... Project Coin has submitted a lot of proposals (almost 70) but only some of them are chosen to Java 7. Why? Briefly, Java is a rich static type system and it has a lot of possible interaction points between different bits of it. Making changes to this type system is prone to creating unexpected surprises. Wow! It is tough, right? Let's take a look what features Project Coi

Java Core - Top 10 Questions Every Developer Should Know

#RandomlyPickedByMe What is the difference between Javascript and Java? Difference between StringBuilder and StringBuffer? Why do I get "SomeType@a3fde" when I print my code? Why is String immutable? Why "equals" method when we have "==" operator? Is List<Dog> a subclass of List<Animal>? Why shouldn't we use raw type? Is Java “pass-by-reference” or “pass-by-value”? What's the advantage of a Java enum versus a class with public static final fields? Why "double x = 0.1 + 0.2" and result of print(x) is 0.30000000000000004? 1. What is the difference between Javascript and Java? Holy crap! (Vietnamese: Thế quái nào lại có câu hỏi ngớ ngẩn vậy chứ?) "Java and Javascript are similar like Car and Carpet are similar." - Greg Hewgill (on StackOverflow) 2. Difference between StringBuilder and StringBuffer String is immutable. StringBuilder and StringBuffer are mutable. StringBuffer is thread-safe. String

Multiple Inheritance of State and Implementation

Today, I was just curious about why an enum can not extend anything else. I took a look on the Oracle document here , and I found the answer is below: "All enums implicitly extend java.lang.Enum. Because a class can only extend one parent (see Declaring Classes), the Java language does not support multiple inheritance of state (see Multiple Inheritance of State, Implementation, and Type), and therefore an enum cannot extend anything else." I have been learned of it before. But, wait a sec...! Why Java does not support multiple inheritance of state? Since I have worked with other programming languages like C++, I was able to make a class extend some other classes. The short answer is to avoid the issues of multiple inheritance of state .  I wonder if other programming languages have these below terms but Java does. Multiple inheritance of state It is the ability to inherit fields from multiple classes. There is a problem and Java avoids it. "For exa