Map<String,Object> map=newHashMap<String,Object>(); // If you're only interested in the keys, you can iterate through thekeySet()of the map:for(String key : map.keySet()) {//...}//If you only need the values, use values():for(Object value : map.values()) {//...}//Final...
System.out.println("HashMap: "+ numbers);// Using entrySet()System.out.println("Key/Value mappings: "+ numbers.entrySet());// Using keySet()System.out.println("Keys: "+ numbers.keySet());// Using values()System.out.println("Values: "+ numbers.values()); } } Output HashMap: {One...
util.*; public class Main { public static void main(String[] args) { HashMap< String, String> hMap = new HashMap< String, String>(); hMap.put("1", "1st"); hMap.put("2", "2nd"); hMap.put("3", "3rd"); Collection cl = hMap.values(); Iterator itr = cl.iterator(); ...
util.*; public class Main { public static void main(String[] args) { HashMap< String, String> hMap = new HashMap< String, String>(); hMap.put("1", "1st"); hMap.put("2", "2nd"); hMap.put("3", "3rd"); Collection cl = hMap.values(); Iterator itr = cl.iterator(); ...
The keySet() method can also be used with the for-each loop to iterate through each key of the hashmap. Example 2: keySet() Method in for-each Loop import java.util.HashMap; class Main { public static void main(String[] args) { // Creating a HashMap HashMap<String, Integer> numbe...
hashmap.put("+1", "USA"); hashmap.containsValue("USA"); //return true hashmap.containsValue("Canada"); //return false 3.5. Iterating through a HashMap We can iterate over the keys, values or entries of a HashMap using the different collection views returned from the following methods...
publicvoiditerateValuesUsingLambda(Map<String, Integer> map){ map.values().forEach(v -> System.out.println(("value: "+ v))); } 5.2. UsingStreamAPI StreamAPI is one significant feature of Java 8. We can use this feature to loop through aMapas well. ...
处理Map 中的空值 假设我们有一个 Map<String, String>,并且我们想要处理其中的空值。 示例代码 代码语言:txt 复制 import java.util.HashMap; import java.util.Map; import java.util.stream.Collectors; public class StreamApiExample { public static void main(String[] args) { Map<String, String>...
From static factory methods on the stream classes, such asStream.of(Object[]),IntStream.range(int, int)orStream.iterate(Object, UnaryOperator); The lines of a file can be obtained fromBufferedReader.lines(); Streams of file paths can be obtained from methods inFiles; ...
而需使用map.keySet() / map.values() /map.entrySet()这几种方式*/publicclassMapIterate{public...