Author: Tirex

java

Writing forEach with java 8 lambda

- by Tirex - Leave a Comment

Let’s take a simple example. It’s easier, probably, and can not be – create a list of numbers and display it on the screen through the simplest cycle:

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List <Integer> numbers = Arrays.asList (1, 2, 3, 4, 5, 6);
 
for (int number: numbers) {
System.out.println (number);
}

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java

How to convert java string array to string with delimiter

- by Tirex - Leave a Comment

Using String.join method (from java 8)

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String[] array = new String[] { "a", "b", "c" };
String joined2 = String.join(",", array);

Using simple for-loop expression

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StringBuilder sb = new StringBuilder();
for (String n : name) {
    if (sb.length() > 0) sb.append(',');
    sb.append("'").append(n).append("'");
}
return sb.toString();

 

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java

How to convert an int to a formatted string in java

- by Tirex - Leave a Comment

Using java.util.formatter

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StringBuilder sb = new StringBuilder();
// Send all output to the Appendable object sb
Formatter formatter = new Formatter(sb, Locale.US);
 
// Explicit argument indices may be used to re-order output.
formatter.format("%4$2s %3$2s %2$2s %1$2s", "a", "b", "c", "d")
// -> " d  c  b  a"
 
// Optional locale as the first argument can be used to get
// locale-specific formatting of numbers.  The precision and width can be
// given to round and align the value.
formatter.format(Locale.FRANCE, "e = %+10.4f", Math.E);
// -> "e =    +2,7183"
 
// The '(' numeric flag may be used to format negative numbers with
// parentheses rather than a minus sign.  Group separators are
// automatically inserted.
formatter.format("Amount gained or lost since last statement: $ %(,.2f",
            balanceDelta);
// -> "Amount gained or lost since last statement: $ (6,217.58)"

See the Formatter docs for other modifiers.

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