Here are 2 code snippets, which are supposed to return the same result, as I used Hashmap in map factory. But the second code snippet doesn't compile in IntelliJ, Both codes work fine in eclipse.

System.out.println method required something where it can call toString, But in intelliJ I get this weird error, Why ?

Compileable Code (Both Eclipse & IntelliJ)

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), Collectors.counting()))); 

Erroneous Code (Works in Eclipse but fails only in IntelliJ)

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), HashMap::new, Collectors.counting()))); 

The error for second snippet in intelliJ

Required type: String Provided: Map <java.lang.String,java.lang.Long> no instance(s) of type variable(s) K, V exist so that HashMap<K, V> conforms to String 

Here are 2 code snippets, which are supposed to return the same result, as I used HashMap in map factory. But the second code snippet doesn't compile in IntelliJ. Both codes work fine in Eclipse.

System.out.println method required something where it can call toString, but in IntelliJ I get this weird error, Why ?

Compileable code (both Eclipse & IntelliJ):

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), Collectors.counting()))); 

Erroneous Code (works in Eclipse but fails only in IntelliJ):

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), HashMap::new, Collectors.counting()))); 

The error for second snippet in IntelliJ

Required type: String Provided: Map <java.lang.String,java.lang.Long> no instance(s) of type variable(s) K, V exist so that HashMap<K, V> conforms to String 

I understand that, this is something related to type inference, But can someone explain this.

Following 2 code snippets supposed to return same result, as I used Hashmap in mapFactory, But the second one doesn't compile. Because the System.out.println method required something of type String, and erroneous code collector is not returning a map where toString can be called. Why ?

Compileable Code

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), Collectors.counting()))); 

Erroneous Code

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), HashMap::new, Collectors.counting()))); 

The error in the second snippet is

Required type: String Provided: Map <java.lang.String,java.lang.Long> no instance(s) of type variable(s) K, V exist so that HashMap<K, V> conforms to String 

Here are 2 code snippets, which are supposed to return the same result, as I used Hashmap in map factory. But the second code snippet doesn't compile in IntelliJ, Both codes work fine in eclipse. 

System.out.println method required something where it can call toString, But in intelliJ I get this weird error, Why ?

Compileable Code (Both Eclipse & IntelliJ)

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), Collectors.counting()))); 

Erroneous Code (Works in Eclipse but fails only in IntelliJ)

 System.out.println(Arrays.stream(str.split(" ")) .collect(Collectors.groupingBy( Function.identity(), HashMap::new, Collectors.counting()))); 

The error for second snippet in intelliJ

Required type: String Provided: Map <java.lang.String,java.lang.Long> no instance(s) of type variable(s) K, V exist so that HashMap<K, V> conforms to String