Tag : java
ASCII Art Java example
A funny Java example to create an ASCII art graphic. The concept is simple, get the image’s rgb color in “integer mode”, later, replace the color’s integer with ascii text. P.S This example is credit to this post and this post. ASCIIArt.java package com.mkyong; import java.awt.Font; import java.awt.Graphics; import… Continue Reading
ascii image java
How to read and parse CSV file in Java
A comma-separated values (CSV) file is just a normal plain-text file, store data in column by column, and split it by a separator (e.g comma “,”). For example : US,United States MY,Malaysia In this tutorial, we show you how to read, parse and print out the values from a csv… Continue Reading
cvs java
Display a list of countries in Java
In this article, we show you how to use the Locale class to play around the list of countries. P.S Tested with JDK 1.6 1. List of Countries The Locale.getISOCountries() will return a list of all 2-letter country codes defined in ISO 3166. ListCountry.java package com.webmitta.model; import java.util.Locale; … Continue Reading
java locale
Java HttpURLConnection follow redirect example
The HttpURLConnection‘s follow redirect is just an indicator, in fact it won’t help you to do the “real” http redirection, you still need to handle it manually. URL obj = new URL(url); HttpURLConnection conn = (HttpURLConnection) obj.openConnection(); conn.setInstanceFollowRedirects(true); //you still need to handle redirect manully. HttpURLConnection.setFollowRedirects(true); 1. Java Http Redirect… Continue Reading
http java
How to get Http Response Header in Java
This example shows you how to get the Http response header values in Java. 1. Get response header from url “mkyong.com” URL obj = new URL("http://mkyong.com"); URLConnection conn = obj.openConnection(); Map<String, List<String>> map = conn.getHeaderFields(); 2. Get key’s (“Server”) value from the headers. Map<String, List<String>> map = conn.getHeaderFields(); List<String> server… Continue Reading
http java
How to get client Ip Address in Java
Normally, you can use servletRequest.getRemoteAddr() to get the client’s IP address that’s accessing your Java web application. String ipAddress = request.getRemoteAddr(); But, if user is behind a proxy server or access your web server through a load balancer (for example, in cloud hosting), the above code will get the IP… Continue Reading
ip address java
How to calculate date and time difference in Java
In this tutorial, we show you 2 examples to calculate date / time difference in Java : Manual time calculation. Joda time library. 1. Manual time calculation Converts Date in milliseconds (ms) and calculate the differences between two dates, with following rules : 1000 milliseconds = 1 second 60 seconds… Continue Reading
date java joda-time time
How to get Google PageRank (PR) in Java
In this example, we will show you how to get Google PageRank (PR) in Java. To request a PageRank for “mkyong.com”, you just need to send following HTTP request : http://toolbarqueries.google.com/tbr?client=navclient-auto&hl=en&ch=6236440745 &ie=UTF-8&oe=UTF-8&features=Rank&q=info:mkyong.com P.S Above URL is used by Google toolbar plugin. The tricky part is following hashing value : ch=6236440745… Continue Reading
java pagerank seo
Search directories recursively for file in Java
Here’s an example to show you how to search a file named “post.php” from directory “/Users/mkyong/websites” and all its subdirectories recursively. FileSearch.java package com.mkyong; import java.io.File; import java.util.ArrayList; import java.util.List; public class FileSearch { private String fileNameToSearch; private List<String> result = new ArrayList<String>(); public String getFileNameToSearch()… Continue Reading
java java.io
How to execute shell command from Java
In Java, you can use the command Runtime.getRuntime().exec to execute shell commands, or any external system command. p = Runtime.getRuntime().exec("host -t a " + domain); p.waitFor(); BufferedReader reader = new BufferedReader(new InputStreamReader( p.getInputStream())); String line = reader.readLine(); while (line != null) { line = reader.readLine(); } 1. IP Address… Continue Reading
bash java How to count duplicated items in Java List
A Java example to show you how to count the total number of duplicated entries in a List, using Collections.frequency and Map. CountDuplicatedList.java package com.mkyong; import java.util.ArrayList; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.List; import java.util.Map; import java.util.Set; import java.util.TreeMap; public class CountDuplicatedList { public static… Continue Reading
java list map Java : getResourceAsStream in static method
A property file in project classpath. config.properties #config file json.filepath = /Users/mkyong/Documents/workspace/SnakeCrawler/data/ 1. Non Static Method Normally, you can access above properties file via getClass().getClassLoader().getResourceAsStream. package com.mkyong.crawler.util; import java.io.IOException; import java.io.InputStream; import java.util.Properties; public class FileHelper { public String getFilePathToSave() { Properties prop = new Properties();… Continue Reading
java properties file Java enum example
Yet another Java enum example, nothing special, just for self-reference. UserStatus.java – User’s status in enum structure package com.mkyong; public enum UserStatus { PENDING("P"), ACTIVE("A"), INACTIVE("I"), DELETED("D"); private String statusCode; private UserStatus(String s) { statusCode = s; } public String getStatusCode() { return statusCode; } … Continue Reading
java How to work with Java 6′s NavigableSet and NavigableMap
You can use latest Java 6′s Collection API to navigate a set and Map collections. These API gives a lot of flexibility to find out required result from the collection. 1. NavigableMap Example package com.example.collection; import java.util.NavigableMap; import java.util.TreeMap; public class NavigableMapDemo { public static void main(String[]… Continue Reading
java java6 How to use reflection to copy properties from Pojo to other Java Beans
Sometimes we need copy properties from a Java class to other, we can do it this manually or with our own reflection implementation, but in this case use us reflection for automate it with a utility from apache Requirements commons-beanutils , you can download from here http://commons.apache.org/beanutils/ commons-loging , you… Continue Reading
java properties reflection