Java Programming II

Project Jigsaw (Java9)

https://infoscis.github.io/2017/03/24/First-steps-with-java9-and-jigsaw-part-1/

https://infoscis.github.io/2017/03/24/First-steps-with-java9-and-jigsaw-part-2/

http://greatkim91.tistory.com/197

 

// String Literal uses String common pool.
// String is immutable object.
// StringBuilder is mutable object.


// + operator (new StringBuilder(String.valueOf(str1)).append(str2).toString();
String str1 = "P";
String str2 = "P";
String str3 = str1 + str2;

// str1.concat(str2) method creates new String
String str4 = str1.concat(str2);



Integer a = 1000, b = 1000;
System.out.println(a == b); // false

// WARNING: JVM tries to save memory
// when the Integer falls in a range (from -128 to 127).
Integer c = 100, d = 100;
System.out.println(c == d); // true


CollectionGenericTest

CollectionIteratorImmutableTest

CollectionEqualsHashcodeContainsTest(updated)

CollectionLambdaStreamTest(updated)