In Java, a utility class is a class that defines a set of methods that perform common functions. This post shows the most frequently used Java utility classes and their most commonly used methods. Both the class list and their method list are ordered by popularity. The data is based on randomly selected 50,000 open source Java projects from GitHub.
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Top 10 Mistakes Java Developers Make
This list summarizes the top 10 mistakes that Java developers frequently make.
Top 10 Questions for Java Regular Expression
This post summarizes the top questions asked about Java regular expressions. As they are most frequently asked, you may find that they are also very useful.
Top 10 Questions about Java Exceptions
This article summarizes the top 10 frequently asked questions and answers about Java exceptions.
Top 5 Questions about C/C++ Pointers
This article summarizes top questions asked about C/C++ pointers on stackoverflow.com. Pointers are the most confusing part of C/C++, those questions use simple examples to explain key pointer concepts.
Top 9 questions about Java Maps
In general, Map is a data structure consisting of a set of key-value pairs, and each key can only appears once in the map. This post summarizes Top 9 FAQ of how to use Java Map and its implemented classes. For sake of simplicity, I will use generics in examples. Therefore, I will just write Map instead of specific Map. But you can always assume that both the K and V are comparable, which means K extends Comparable and V extends Comparable.
Top 10 questions about Java Collections
The following are the most popular questions of Java collections asked and discussed on Stackoverflow. Before you look at those questions, it’s a good idea to see the class hierarchy diagram. 1. When to use LinkedList over ArrayList? ArrayList is essentially an array. Its elements can be accessed directly by index. But if the array … Read more
Top 8 Diagrams for Understanding Java
A diagram is sometimes worth 1000 words. The following diagrams are from Java tutorials on Program Creek, they have received the most votes so far. Hopefully, they can help you review what you already know. If the problem is not clear by the diagram itself, you may want to go to each article to take a further took.
Top 10 questions of Java Strings
The following are top 10 frequently asked questions about Java Strings.
1. How to compare strings? Use “==” or use equals()?
In brief, “==” tests if references are equal and equals() tests if values are equal. Unless you want to check if two strings are the same object, you should always use equals().
Top 10 Methods for Java Arrays
The following are top 10 methods for Java Array. They are the most voted questions from stackoverflow. 0. Declare an array String[] aArray = new String[5]; String[] bArray = {"a","b","c", "d", "e"}; String[] cArray = new String[]{"a","b","c","d","e"};String[] aArray = new String[5]; String[] bArray = {"a","b","c", "d", "e"}; String[] cArray = new String[]{"a","b","c","d","e"}; 1. Print an … Read more
Top 8 Tools for Natural Language Processing
English text is used almost everywhere. It would be the best if our system can understand and generate it automatically. However, understanding natural language is a complicated task. It is so complicated that a lot of researchers dedicated their whole life to do it. Nowadays, a lot of tools have been published to do natural … Read more
Frequently Used Methods of Java HashMap
HashMap is very useful when a counter is required.
HashMap<String, Integer> countMap = new HashMap<String, Integer>(); //.... a lot of a's like the following if(countMap.keySet().contains(a)){ countMap.put(a, countMap.get(a)+1); }else{ countMap.put(a, 1); } |
100 High-Quality Java Developers’ Blogs
The intent of this page is to collection the best 100 Java blogs and help programmers to find good blog posts to read. Some of these blogs may not be written by Java developers, but Java developers should find it useful or interesting. Reading those blogs should be fun and often bring some fresh ideas. … Read more
8 Things Programmers Can Do at Weekends
Weekends are an important time to unplug from the day-to-day job and get recharged. They are also a good chance to think more deeply about things. Software programmer (developer or engineer) is a special occupation comparing to others, even though many jobs require the use of computers. Inspired by “14 Things Successful People Do On … Read more