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string methods

String Arrays

String[] myArray;

ArrayLists

java.util.ArrayList

ArrayList<String> flexibleList = new ArrayList<String>();

char to String

String.valueOf(char)

public static final String charToString(char c) {
    return Character.toString(c);
}

String to char

charAt(int)

public static final char StringToChar(String str) {
    return str.charAt(0);
}

String to char array

char[] chararray = str.toCharArray();

getChars

instance.getChars(int start, int end, array start, int destination)

mystr.getChars(0, 16, chararr, 0);

Streaming - char() method

Creates a Stream from a String object

Character[] arraychars = str.chars()
                            .mapToObj(c -> (char) c)
                            .toArray(Character[]::new);

String Array to String

Arrays.toString();

// convert an array to string
String str = Arrays.toString(strarray);

StringBuilder() and append()

StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < strarray.length; ++i) {
    stringBuilder.append(strarray[i] + " ");
}

String Joiner

import java.util.StringJoiner;
StringJoiner stringJoiner = new StringJoiner(";;;", "[", "]");

Stream and collector

import java.util.stream.*;
import java.util.Arrays;
return Stream.of(strarray).collect(Collectors.joinint());

String to String Array

split()

String[] strarray = str.split(",");

pattern.split()

import java.util.regex.Pattern;
String splitpattern = "\\s\\s";
Pattern pattern = Pattern.compile(splitpattern);

String Tokenizer Class

import java.util.StringTokenizer;
StringTokenizer tokenizer = new StringTokenizer(str);
String[] strarray = new String[tokenizer.countTokens()];

// Add tokens to an array
int i = 0;
while (tokenizer.hasMoreTokens()) {
    strarray[i] = tokenizer.nextToken();
    ++i;
}

Java 8+ methods

char charAt(int index);
int compareTo(String anotherString);
String concat(String str);
int hashCode();
int indexOf
int length();
String replace
String replaceAll
String[] split(String regex);
boolean startsWith(String prefix);
String substring(int beginIndex);
String toLowerCase();
String toUpperCase();
String trim();

Java 11+ Methods

isBlank();
lines(); // returns a stream containing a collection of all * substrings split by lines(needs java.util.stream.Collectors)
strip(); // Removes all white space from strings, unicode-aware
repeat(int); // repeats a string(int) times

Java 13+ Methods

Text Block formatting

String block = """
Brain went on to say that
'Text blocks are much more readable
And much easier to debug or follow'
""";