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https://www.geeksforgeeks.org/java-8-collectors-counting-with-examples/ Collectors counting() method is used to count the number of elements passed in 阅读全文
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https://www.geeksforgeeks.org/collectors-groupingby-method-in-java-with-examples/ The groupingBy() method of Collectors class in Java are used for gro 阅读全文
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https://www.geeksforgeeks.org/enum-in-java/ Enumerations serve the purpose of representing a group of named constants in a programming language. For e 阅读全文
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https://www.geeksforgeeks.org/comparable-vs-comparator-in-java/ Java provides two interfaces to sort objects using data members of the class: Comparab 阅读全文
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https://www.geeksforgeeks.org/equals-hashcode-methods-java/ Java.lang.object has two very important methods defined: public boolean equals(Object obj) 阅读全文
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https://www.geeksforgeeks.org/stream-in-java/ Introduced in Java 8, the Stream API is used to process collections of objects. A stream is a sequence o 阅读全文
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https://www.geeksforgeeks.org/generics-in-java/ Generics means parameterized types. The idea is to allow type (Integer, String, … etc., and user-defin 阅读全文