How-to articles, tricks, and solutions about JAVA

To find out which keystore the Java Virtual Machine (JVM) is using, you can use the javax.net.ssl.KeyManagerFactory class and the getDefaultAlgorithm method.

To pretty print XML from Java, you can use the javax.xml.transform.Transformer class from the Java XML Transformer API.

In Java, you can use the javafx.util.Pair class to represent a pair or 2-tuple.

In Java, there is no native support for multiline strings.

To encode and decode a string in Base64 in Java, you can use the java.util.Base64 class.

To determine whether you are running in a 64-bit JVM or a 32-bit JVM from within a Java program, you can use the sun.arch.data.model system property.

To get the length of a 2D array in Java, you can use the length field of the array.

To convert a stack trace to a string in Java, you can use the printStackTrace() method of the Throwable class, which prints the stack trace to a PrintWriter.

If you are using MySQL JDBC Driver version 5.1.33 and you are experiencing issues with time zones, there are a few things you can try:

To update an entity using Spring Data JPA, you will need to follow these steps:

You can use the toArray() method of the List interface to convert a List<Integer> to an int[] in Java.

To import the javax.servlet or jakarta.servlet API in an Eclipse project, follow these steps:

There are a few possible reasons why IntelliJ might show a "Cannot resolve symbol" error while still being able to compile your code.

To create a dictionary (or map) in Java, you can use the Map interface and its implementing classes.

To convert a List<V> into a Map<K, V> in Java 8, you can use the toMap() method of the Collectors class from the java.util.stream package.

To get the current class name in Java, you can use the getClass() method of the Object class, which returns a Class object that represents the runtime class of the object.

To download and save a file from the Internet using Java, you can use the URL and URLConnection classes from the java.net package.

There are several Java GUI frameworks available, each with its own strengths and weaknesses.

To connect a Java application to a MySQL database, you need to use the JDBC (Java Database Connectivity) API.

To connect to an Oracle database using a service name instead of a SID (System Identifier), you can use the thin driver and specify the connection URL in the following format:

It is generally not a good idea to intentionally create a memory leak in Java.

To create a directory in Java, you can use the mkdir() method of the File class.

To get the last character of a string in Java, you can use the charAt() method of the String class, which returns the character at a specific index in the string.

To convert an array to a Set in Java, you can use the Arrays.asList() method to create a List from the array, and then use the List.toSet() method to create a Set from the List.

To sort the values of a Map by key in Java, you can use the TreeMap class, which is a Map implementation that maintains its entries in ascending key order.