JAVA: Contar ocurrencias de un carácter en una cadea - https://es.stackoverflow.com/q/181420/29967, Java

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/* JAVA: Contar ocurrencias de un carácter en una cadea - https://es.stackoverflow.com/q/181420/29967*/

import java.util.*;
import java.lang.*;

class Rextester
{  
    public static void main(String args[])
    {
        String testString = "+0+4+3+4+5";
        int replace = testString.length() - testString.replace("+", "").length();
        System.out.println("1. Con replace = " + replace);

int replaceAll = testString.replaceAll("[^+]", "").length();
        System.out.println("2. Con replaceAll = " + replaceAll);

int replaceAllCase2 = testString.length() - testString.replaceAll("\\+", "").length();
        System.out.println("3. Con replaceAll (2º caso) = " + replaceAllCase2);

int split = testString.split("\\+",-1).length-1;
        System.out.println("4. Con split = " + split);

long java8 = testString.chars().filter(ch -> ch =='+').count();
        System.out.println("5. Con Lambda (Java8) = " + java8);

long java8Case2 = testString.codePoints().filter(ch -> ch =='+').count();
        System.out.println("6. Con Lambda (2º caso) = " + java8Case2);

int stringTokenizer = new StringTokenizer(" " +testString + " ", "+").countTokens()-1;
        System.out.println("7. Con stringTokenizer = " + stringTokenizer);       
        
        
    }
}

[ + ] Show input
Compilation time: 0.93 sec, absolute running time: 0.3 sec, cpu time: 0.43 sec, memory peak: 25 Mb, absolute service time: 1,24 sec

JAVA: Contar ocurrencias de un carácter en una cadea - https://es.stac...