I have introduced the method reference in the previous tutorial, in this tutorial, I introduce you another new concept: constructor reference. Like the method reference, the constructor reference is used to abbreviate the Lambda Expression expression. How is it in details? Suppose you are working… Read More
In the Lambda Expression tutorials, I introduced you to the Functional Interface and its importance when using Lambda Expression in Java code. In this tutorial, I will talk more about Functional Interface! Definition of Functional Interface OK, let me first talk about the definition of… Read More
Type Inference in Java is a Java Compiler’s ability base on the declaration, the calling to determine the datatype, without explicitly declaring it, reducing redundancy code. For you to understand more, I will take an example as follows. Assuming you are working with the List… Read More
In Java, we know that two types of data are primitive and object. So, Lambda Expression is defined as an anonymous function, what is its data type? In this tutorial, let’s find out together! OK, as I mentioned earlier, Lambda Expression is used with a… Read More
To filter a Map using Stream and Lambda Expression in Java, we will use the filter() method of Stream object which will be retrieved from Entry object of Map object with Lambda Expression as filter a List. How is it in details? Let learn together in… Read More
Stream is a new Java object, was introduced from Java 8. It helps us can manipulate on collections and arrays easier and more efficient. So what is it? In this article, I will introduce with you all about the Stream in Java. First, consider the… Read More
Since Java 8, we have ability to convert an object into another type by using map() method of Stream object with Lambda Expression. In this tutorial, I will show to you all some examples about it. Note that, map() method is an intermediate operation in… Read More
Normally, before Java 8, when we want to filter a List, we will iterate through the List and base on the condition we want to filter, we can have a new List on demand. For example, I have a List containing some student names as… Read More
Normally, before Java 8, when we want to sort a List object, we will use Comparator object. For example:
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package com.huongdanjava.javaexample; import java.util.ArrayList; import java.util.Collections; import java.util.Comparator; import java.util.List; public class Example { public static void main(String[] args) { List<String> names = new ArrayList<>(); names.add("Thanh"); names.add("Khanh"); names.add("Tan"); Collections.sort(names, new Comparator<String>() { @Override public int compare(String s1, String s2) { return s1.compareTo(s2); } }); for (String s : names) { System.out.println(s); } } } |
Result: Since Java 8, we have another way to do the sorting a List object. That is: using sort() method in List object with Lambda… Read More
In this tutorial, I will show you all how using Lambda Expression to foreach a Map object in Java. OK, let’s get started! Same like List object, the forEach () method is also added to the Map object since Java 8, which gives us more… Read More
