[Java in NetBeans] Lesson 12. Arrays

这个课程的参考视频和图片来自youtube。

主要学到的知识点有：

1. Array: container that holds a fixed number of values of the same type, can be access by index.

• Create a string array and initialize the elements one by one. Index will be start from 0 to size -1.

String[] names = new String[3];
names[0] = "Tom";
names[1] = "Bob";
names[2] = "Joe";
// Below is a wrong comment
names[3] = "wrong!" // Will show error because out of the index.   

• Automatic detect the size of the array

String[] names = new String[]{"Tom", "Bob", "Joe"};

2. Go through the elements in the array.

• for loop using index

for ( int i = 0; i < names.length; i ++){
System.out.printf("%s ", names[i]);
}

// the result will be like this
Tom, Bob, Joe   

• for loop using "foreach"

for ( String each : names){
System.out.printf("%s ", each);
}

// the result will be like this
Tom, Bob, Joe