How-to articles, tricks, and solutions about JAVA

To remove all white spaces from a string in Java, you can use the replaceAll method of the String class, along with a regular expression that matches any white space character (including spaces, tabs, and line breaks):

There are several ways to remove line breaks from a file in Java.

To remove a single character from a string by its index in Java, you can use the StringBuilder.deleteCharAt() method. Here's an example of how to use it:

There are a few ways to remove the last character from a string in Python. Here are three approaches you can use:

The java.lang.NoClassDefFoundError: javax/xml/bind/JAXBException error occurs when the Java class javax.xml.bind.JAXBException is not found on the classpath. This class is part of the Java Architecture for XML Binding (JAXB) API, which is used for parsing

To respond with an HTTP 400 error in a Spring MVC controller method that returns a String, you can throw a ResponseStatusException with a status of BAD_REQUEST.

There are a few ways you can return multiple values from a Java method:

There are a few different ways to return multiple values from a method in Java:

There are several ways to round a number to n decimal places in Java:Using DecimalFormat

To run a JAR file, you need to have Java installed on your computer. If you don't have it installed, you can download it from the Oracle website.

In JUnit 4, you can use the @FixMethodOrder annotation to specify the order in which test methods should be executed.

To run a Unix shell script from Java code, you can use the Runtime.getRuntime().exec() method to execute the script.

To select a dropdown value in Selenium WebDriver using Java, you can use the selectByValue or selectByVisibleText methods of the Select class.

In Java, you can send an HTTP request using the java.net.URL and java.net.HttpURLConnection classes.

To set a timer in Java, you can use the java.util.Timer class.

To set the JAVA_HOME environment variable on Mac OS X 10.9, follow these steps:

To set the JAVA_HOME environment variable in Linux for all users, you will need to add a line to the /etc/environment file.

To set the JAVA_HOME environment variable on Windows 7, follow these steps:<br>

To set the default Java (JDK) version on macOS, you can use the java_home command line tool. Here's how:

To set the selected item of a Spinner by value (not by position) in Android, you can use the setSelection() method of the Spinner class and pass it the index of the item that you want to select.

To set a specific Java version for Maven, you can specify the maven.compiler.source and maven.compiler.target properties in the pom.xml file.

To set environment variables for Java in Windows:

To set the time zone of a java.util.Date object in Java, you can use the Calendar class.

If you are getting the "Could not create the Java virtual machine" error when trying to launch a Java program, it means that the Java Virtual Machine (JVM) is unable to allocate enough memory to run the program.

The java.lang.NullPointerException error is thrown when an application attempts to use an object reference that has the null value. This usually occurs when you try to call a method or access a field of an object that is null