HashMap Stream and Filtering Example

HashMap can be filtered with the filter() method of the Java Stream API.

HashMap Stream and Filtering Example

package com.javaguides.collections.hashmapexamples; import java.util.HashMap; import java.util.Map; import java.util.stream.Collectors; public class IterateOverHashMap { public static void main(String[] args) { Map<String, String> countryISOCodeMapping = new HashMap<>(); countryISOCodeMapping.put("India", "IN"); countryISOCodeMapping.put("United States of America", "US"); countryISOCodeMapping.put("Russia", "RU"); countryISOCodeMapping.put("Japan", "JP"); countryISOCodeMapping.put("China", "CN"); Map<String, String> filteredCapitals = countryISOCodeMapping.entrySet().stream() .filter(map -> map.getValue().length() == 2) .collect(Collectors.toMap(Map.Entry::getKey, Map.Entry::getValue)); filteredCapitals.entrySet().forEach(System.out::println); } }

Output

China=CN Japan=JP United States of America=US Russia=RU India=IN

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