Q : Is there a function in Java to retrieve the Tomcat (Catalina) home directory? A : Yes, Tomcat home directory or Catalina directory is stored at the Java System Property environment. If the Java web application is deployed into Tomcat web server, we can get the Tomcat directory with the following command System.getProperty("catalina.base");
A Java example to show you how to convert a Char into a String and vise verse. ConvertCharToString.java package com.mkyong.utils; public class ConvertCharToString { public static void main(String[] args) { String website = "https://mkyong.com"; //convert a String into char char charH = website.charAt(0); //h char charP = website.charAt(3);//p char charM = website.charAt(11);//m System.out.println(charH); System.out.println(charP); System.out.println(charM); …
Often times, we need to “preload” an image into browser’s cache for performance concern. For instance, we have a mouseover event and the image needs to be update without any delay. This “Preloading” stuff can be achieved in two ways , either JavaScript or HTML code. Javascript We can “preload” an image with the following …
JUnit 4 and TestNG are both very popular unit test framework in Java. Both frameworks look very similar in functionality. Which one is better? Which unit test framework should I use in Java project? Here I did a feature comparison between JUnit 4 and TestNG. 1. Annotation Support The annotation supports are implemented in both …
In JUnit, you can pass the parameters into the unit test method via the following methods : Constructor Fields injection via @Parameter P.S Tested with JUnit 4.12 1. MatchUtils – Test with multiple parameters A simple add operation. MathUtils.java package com.mkyong.examples; public class MathUtils { public static int add(int a, int b) { return a …
In JUnit, you can run multiple test cases with @RunWith and @Suite annotation. Refer to the following examples : SuiteAbcTest.java package com.mkyong; import org.junit.Test; import org.junit.runner.RunWith; import org.junit.runners.Suite; @RunWith(Suite.class) @Suite.SuiteClasses({ Exception1Test.class, //test case 1 TimeoutTest.class //test case 2 }) public class SuiteAbcTest { //normally, this is an empty class } P.S Tested with JUnit 4.12 …
If a test is taking longer than a defined “timeout” to finish, a TestTimedOutException will be thrown and the test marked failed. See the following example : P.S Tested with JUnit 4.12 1. Timeout Example This timeout example only applies to a single test method. And the timeout value is in milliseconds. TimeoutTest.java package com.mkyong; …
In JUnit, to ignore a test, just add a @Ignore annotation before or after the @Test method. P.S Tested with JUnit 4.12 IgnoreTest.java package com.mkyong; import org.junit.Ignore; import org.junit.Test; import static org.hamcrest.CoreMatchers.is; import static org.junit.Assert.assertThat; public class IgnoreTest { @Test public void testMath1() { assertThat(1 + 1, is(2)); } @Ignore @Test public void testMath2() { …
In JUnit, there are 3 ways to test the expected exceptions : @Test, optional ‘expected’ attribute Try-catch and always fail() @Rule ExpectedException P.S Tested with JUnit 4.12 1. @Test expected attribute Use this if you only want to test the exception type, refer below : Exception1Test.java package com.mkyong; import org.junit.Test; import java.util.ArrayList; public class Exception1Test …
Here’re some basic JUnit annotations you should understand: @BeforeClass – Run once before any of the test methods in the class, public static void @AfterClass – Run once after all the tests in the class have been run, public static void @Before – Run before @Test, public void @After – Run after @Test, public void …
In TestNG, we use dependOnMethods and dependsOnGroups to implement dependency testing. If a dependent method is fail, all the subsequent test methods will be skipped, NOT failed. 1. dependOnMethods Example A simple example, “method2()” is dependent on “method1()”. 1.1 If method1() is passed, method2() will be executed. App.java package com.mkyong.testng.examples.dependency; import org.testng.annotations.Test; public class App …
In this tutorial, we will show you how to pass parameters into a @Test method, via XML @Parameters or @DataProvider. 1. Passing Parameters with XML In this example, the properties filename is passing from testng.xml, and inject into the method via @Parameters. TestParameterXML.java package com.mkyong.testng.examples.parameter; import java.io.IOException; import java.io.InputStream; import java.sql.Connection; import java.sql.DriverManager; import java.util.Properties; …
In this tutorial, we will show you how to run multiple TestNG test cases (classes) together, aka suite test. 1. Test Classes Review following three test classes. TestConfig.java package com.mkyong.testng.examples.suite; import org.testng.annotations.AfterSuite; import org.testng.annotations.AfterTest; import org.testng.annotations.BeforeSuite; import org.testng.annotations.BeforeTest; //show the use of @BeforeSuite and @BeforeTest public class TestConfig { @BeforeSuite public void testBeforeSuite() { System.out.println("testBeforeSuite()"); …
The following code is a JQuery javascript which will refresh the captcha image automatically wherever user clicked on it. The code is working fine in FireFox. However, when i test it in Internet explorer 6 or 7, i hit the following Active X controls warning. Your security settings do not allow Web sites to use …
In this tutorial, we will show you how to perform timeout test in TestNG. The “timeout” means if a unit test is taking longer than a specified number of milliseconds to finish, TestNG will abort it and market it as failed. This “timeout” can also use for performance test, to ensure the method is returned …
For Java libraries that are not available in the Maven Central or other Maven repositories, we need to install it into our Maven Local repository in order to use it as a project dependencies. Note You may interest at this How to add Oracle JDBC driver in your Maven local repository In this tutorial, we …
In this tutorial, we will show you how to ignore a test method with @Test(enabled = false). TestIgnore.java package com.mkyong.testng.examples.ignore; import org.testng.Assert; import org.testng.annotations.Test; public class TestIgnore { @Test //default enable=true public void test1() { Assert.assertEquals(true, true); } @Test(enabled = true) public void test2() { Assert.assertEquals(true, true); } @Test(enabled = false) public void test3() { …
In this tutorial, we will show you how to use the TestNG expectedExceptions to test the expected exception throws in your code. 1. Runtime Exception This example shows you how to test a runtime exception. If the method divisionWithException () throws a runtime exception – ArithmeticException, it will be passed. TestRuntime.java package com.mkyong.testng.examples.exception; import org.testng.annotations.Test; …
In TestNG, we can use the following annotations to do the configuration for your test class, like setup / clean a database, preparing the dummy data, deploy / shut down the server and etc. @BeforeSuite – For suite test, run before all tests in this suite have run. @AfterSuite – For suite test, run after …
This article shows a handy Java class that uses System.getProperty("os.name") to detect which type of operating system (OS) you are using now. 1. Detect OS (Original Version) This code can detect Windows, Mac, Unix, and Solaris. OSValidator.java package com.mkyong.system; public class OSValidator { private static String OS = System.getProperty("os.name").toLowerCase(); public static void main(String[] args) { …
When i integrate Hudson and PMD together to run the PMD static code analysis process in my web project. I hit the following error message. By the way , i’m using Maven 2 to mange my web project. Caused by: net.sourceforge.pmd.ast.ParseException: Can’t use JDK 1.5 for loop syntax when running in JDK 1.4 mode! at …
CSS Padding property setting is confusing sometime, because it can accept 1 value, 2 values , 3 or 4 values together. For example, all the padding property setting below is valid. padding: 10px; padding: 10px 8px; padding: 10px 8px 10px; padding: 10px 8px 10px 9px; CSS Padding Rule. 1) CSS padding order is follow clockwise …
In Java, the InputStreamReader accepts a charset to decode the byte streams into character streams. We can pass a StandardCharsets.UTF_8 into the InputStreamReader constructor to read data from a UTF-8 file. import java.nio.charset.StandardCharsets; //… try (FileInputStream fis = new FileInputStream(file); InputStreamReader isr = new InputStreamReader(fis, StandardCharsets.UTF_8); BufferedReader reader = new BufferedReader(isr) ) { String str; …
In Java, the OutputStreamWriter accepts a charset to encode the character streams into byte streams. We can pass a StandardCharsets.UTF_8 into the OutputStreamWriter constructor to write data to a UTF-8 file. try (FileOutputStream fos = new FileOutputStream(file); OutputStreamWriter osw = new OutputStreamWriter(fos, StandardCharsets.UTF_8); BufferedWriter writer = new BufferedWriter(osw)) { writer.append(line); } In Java 7+, many …
The focus() method is used to give focus to a textbox, or other html components. Here is a simple example to make a textbox focus automatically after page load. focus is not working in IE The above code is working fine in Firefox (FF), but not in Internet Explorer (IE). Actually the IE is supporting …
The getElementsByName() method is use to get the element by name. However be aware of the getElementsByName() method always return an array as output. Caution The method always return an array, and we have to use [] to access the value. For example alert(document.getElementsByName(“myInput”).value); It will prompt out an undefined value alert(document.getElementsByName(“myInput”)[0].value); It will prompt …
The ‘unchecked warnings’ is quite popular warning message in Java. However, if you insist this is an invalid warning, and there are no ways to solve it without compromising the existing program functionality. You may just use @SuppressWarnings(“unchecked”) to suppress unchecked warnings in Java. 1. In Class If applied to class level, all the methods …
Here is a simple ResourceBundle message files hello = "Hi \n \n Good Morning \n \n thanks" If we retrieve the resource bundle key “hello”, we expected the result as following Hi Good Morning thanks Unfortunately, Java doesn’t work in this way, “String” will not translate the \n into new line by default. If we …
In JavaScript, you can use getElementById() fucntion to get any prefer HTML element by providing their tag id. Here is a HTML example to show the use of getElementById() function to get the DIV tag id, and use InnerHTML() function to change the text dynamically. HTML… <html> <head> <title>getElementById example</title> <script type="text/javascript"> function changeText(text) { …
The “context-param” tag is define in “web.xml” file and it provides parameters to the entire web application. For example, store administrator’s email address in “context-param” parameter to send errors notification from our web application. web.xml <context-param> <param-name>AdministratorEmail</param-name> <param-value>[email protected]</param-value> </context-param> We can get the above “AdministratorEmail” context-param value with the following java code. String email= getServletContext().getInitParameter("AdministratorEmail"); …
In Maven, you can define a system property -Dmaven.test.skip=true to skip the entire unit test. By default, when building project, Maven will run the entire unit tests automatically. If any unit tests is failed, it will force Maven to abort the building process. In real life, you may STILL need to build your project even …
This is always advisable to encode URL or form parameters; plain form parameter is vulnerable to cross site attack, SQL injection and may direct our web application into some unpredicted output. A URL String or form parameters can be encoded using the URLEncoder class – static encode (String s, String enc) method. For example, when …
In Java, we can use Apache commons-text to escape the special characters in HTML entities. Special characters as follow: < > ” & pom.xml <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-text</artifactId> <version>1.8</version> </dependency> EscapeSpecialChar.java package com.mkyong.html; import org.apache.commons.text.StringEscapeUtils; // @deprecated as of 3.6, use commons-text StringEscapeUtils instead //import org.apache.commons.lang3.StringEscapeUtils; public class EscapeSpecialChar { public static void main(String[] args) { …
This article shows how to convert Java objects to from JSON using Gson. Table of contents: 1. Download Google Gson 2. Gson Basic Usages 3. Java Object 4. Convert Object to JSON using Gson 5. Converts JSON to Java Object using Gson 6. Modify JSON with JsonElement 7. Converts Json Array to List objects 8. …
Oftentimes, we use SSH to remote access into the server to run a Java program. The problem is, we can’t type anything After the Java program is executed like this : $ java -jar example.jar In addition, when the remote access session is expired or terminated, the executed Java program will be killed. Solution To …
My monthly PCB income tax is increased much since march 2009, HR told me that Malaysia monthly income tax PCB deduction rate is changed since year 2009. Income tax PCB calculation Here’s the calculation. 1. Find your PCB amount in this Income tax PCB 2009 Chart 2. Calculate your taxable salary – Taxable Salary = …
In Java, we can use str.getBytes(StandardCharsets.UTF_8) to convert a String into a byte[]. String str = "This is a String"; // default charset, a bit dangerous byte[] output1 = str.getBytes(); // in old days, before java 1.7 byte[] output2 = str.getBytes(Charset.forName("UTF-8")); // the best , java 1.7+ , new class StandardCharsets byte[] output3 = str.getBytes(StandardCharsets.UTF_8); …
In Java, we can use new String(bytes, StandardCharsets.UTF_8) to convert a byte[] to a String. // string to byte[] byte[] bytes = "hello".getBytes(StandardCharsets.UTF_8); // byte[] to string String s = new String(bytes, StandardCharsets.UTF_8); Table of contents 1. byte[] in text and binary data 2. Convert byte[] to String (text data) 3. Convert byte[] to String …
In this article, we show you how to use Java Cryptography Extension (JCE) to encrypt or decrypt a text via Data Encryption Standard (DES) mechanism. 1. DES Key Create a DES Key. KeyGenerator keygenerator = KeyGenerator.getInstance("DES"); SecretKey myDesKey = keygenerator.generateKey(); 2. Cipher Info Create a Cipher instance from Cipher class, specify the following information and …
Often times, you may to use “mvn eclipse:eclipse -Dwtpversion=1.5” command to create a web project for Eclipse IDE, but you may encounter the following error messages. Unsupported WTP version: 1.5. This plugin currently supports only the following versions: 1.0 R7 D:\mkyong>mvn eclipse:eclipse -Dwtpversion=1.5 [INFO] Scanning for projects… [INFO] Searching repository for plugin with prefix: ‘eclipse’. …