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Display Prime Numbers Between Intervals Using FunctionDisplay Armstrong Numbers Between Intervals Using FunctionCheck Whether a Number can be Expressed as Sum of Two Prime NumbersFind the Sum of Natural Numbers using RecursionFind Factorial of a Number Using RecursionFind G.C.D Using RecursionConvert Binary Number to Decimal and vice-versaConvert Octal Number to Decimal and vice-versaConvert Binary Number to Octal and vice-versaReverse a Sentence Using Recursioncalculate the power using recursionArrays
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To understand this example, you should have the knowledge of the following Java programming topics:
Example: Lookup enum by string value
public class EnumString {
public enum TextStyle {
BOLD, ITALICS, UNDERLINE, STRIKETHROUGH
}
public static void main(String[] args) {
String style = "Bold";
TextStyle textStyle = TextStyle.valueOf(style.toUpperCase());
System.out.println(textStyle);
}
}
Output
BOLD
In the above program, we have an enum TextStyle which represents the different styles a block of text can have, i.e. Bold, Italics, Underline, Strikethrough.
We also have a string named style which holds the current style we want. However, it is not in all-caps.
We then use the enum TextStyle’s valueOf() method to pass the style and get the enum value we require.
Since valueOf() takes a case-sensitive string value, we had to use the toUpperCase() method to convert the given string to upper case.
If, instead, we’d used:
TextStyle.valueOf(style)
the program would’ve thrown an exception No enum constant EnumString.TextStyle.Bold.