Java Language
- Getting started with Java Language
- Top 10 Java Errors with Solutions
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- 2D Graphics in Java
- Alternative Collections
- Annotations
- Apache Commons Lang
- AppDynamics and TIBCO BusinessWorks Instrumentation for Easy Integration
- Applets
- Arrays
- Asserting
- Atomic Types
- Audio
- Autoboxing
- Basic Control Structures
- Benchmarks
- BigDecimal
- BigInteger
- Bit Manipulation
- BufferedWriter
- ByteBuffer
- Bytecode Modification
- C++ Comparison
- Calendar and its Subclasses
- Character encoding
- Choosing Collections
- Class - Java Reflection
- Classes and Objects
- Classloaders
- Collection Factory Methods
- Collections
- Command line Argument Processing
- Common Java Pitfalls
- Comparable and Comparator
- CompletableFuture
- Concurrent Collections
- Concurrent Programming (Threads)
- Console I/O
- Constructors
- Converting to and from Strings
- Creating Images Programmatically
- Currency and Money
- Date Class
- Dates and Time (java.time.*)
- Default Methods
- Dequeue Interface
- Disassembling and Decompiling
- Documenting Java Code
- Dynamic Method Dispatch
- Encapsulation
- Enum Map
- Enum starting with number
- Enums
- EnumSet class
- Exceptions and exception handling
- Executor, ExecutorService and Thread pools
- Expressions
- File I/O
- FileUpload to AWS
- Fluent Interface
- FTP (File Transfer Protocol)
- Functional Interfaces
- Generating Java Code
- Generics
- Getters and Setters
- Hashtable
- HttpURLConnection
- Immutable Class
- Immutable Objects
- Inheritance
- InputStreams and OutputStreams
- Installing Java (Standard Edition)
- Configuring and switching Java versions on Linux using alternatives
- Installing a Java JDK on Linux
- Installing a Java JDK on macOS
- Installing a Java JDK or JRE on Windows
- Installing oracle java on Linux with latest tar file
- Java release and version naming
- Post-installation checking and configuration on Linux
- Selecting an appropriate Java SE release
- Setting %PATH% and %JAVA_HOME% after installing on Windows
- What do I need for Java Development
- Interfaces
- Iterator and Iterable
- Java Agents
- Java Compiler - 'javac'
- Java deployment
- Java Editions, Versions, Releases and Distributions
- Java Floating Point Operations
- Java Memory Management
- Java Memory Model
- Java Native Access
- Java Native Interface
- Java Performance Tuning
- Java Pitfalls - Exception usage
- Java Pitfalls - Language syntax
- Java Pitfalls - Nulls and NullPointerException
- Java Pitfalls - Performance Issues
- Java Pitfalls - Threads and Concurrency
- Java plugin system implementations
- Java Print Service
- Java SE 7 Features
- Java SE 8 Features
- Java Sockets
- Java Virtual Machine (JVM)
- JavaBean
- JAXB
- JAX-WS
- JMX
- JNDI
- JShell
- JSON in Java
- Just in Time (JIT) compiler
- JVM Flags
- JVM Tool Interface
- Lambda Expressions
- LinkedHashMap
- List vs SET
- Lists
- Literals
- Local Inner Class
- Localization and Internationalization
- LocalTime
- log4j / log4j2
- Logging (java.util.logging)
- Maps
- Modules
- Multi-Release JAR Files
- Nashorn JavaScript engine
- Nested and Inner Classes
- Networking
- New File I/O
- NIO - Networking
- Non-Access Modifiers
- NumberFormat
- Object Class Methods and Constructor
- Object Cloning
- Object References
- Operators
- Optional
- Oracle Official Code Standard
- Packages
- Parallel programming with Fork/Join framework
- Polymorphism
- Preferences
- Primitive Data Types
- Process
- Properties Class
- Queues and Deques
- Random Number Generation
- Readers and Writers
- Recursion
- Reference Data Types
- Reference Types
- Reflection API
- Regular Expressions
- Remote Method Invocation (RMI)
- Resources (on classpath)
- RSA Encryption
- Runtime Commands
- Scanner
- Secure objects
- Security & Cryptography
- Security & Cryptography
- SecurityManager
- Serialization
- ServiceLoader
- Sets
- Singletons
- Sockets
- SortedMap
- Splitting a string into fixed length parts
- Stack-Walking API
- Streams
- String Tokenizer
- StringBuffer
- StringBuilder
- Strings
- sun.misc.Unsafe
- super keyword
- The Classpath
- The Java Command - 'java' and 'javaw'
- The java.util.Objects Class
- ThreadLocal
- TreeMap and TreeSet
- Type Conversion
- Unit Testing
- Using Other Scripting Languages in Java
- Using the static keyword
- Using ThreadPoolExecutor in MultiThreaded applications.
- Varargs (Variable Argument)
- Visibility (controlling access to members of a class)
- WeakHashMap
- XJC
- XML Parsing using the JAXP APIs
- XML XPath Evaluation
- XOM - XML Object Model
Java Language Installing Java (Standard Edition) Configuring and switching Java versions on Linux using alternatives
Example
Using Alternatives
Many Linux distributions use the alternatives command for switching between different versions of a command. You can use this for switching between different versions of Java installed on a machine.
-
In a command shell, set $JDK to the pathname of a newly installed JDK; e.g.
$ JDK=/Data/jdk1.8.0_67 -
Use
alternatives --installto add the commands in the Java SDK to alternatives:$ sudo alternatives --install /usr/bin/java java $JDK/bin/java 2 $ sudo alternatives --install /usr/bin/javac javac $JDK/bin/javac 2 $ sudo alternatives --install /usr/bin/jar jar $JDK/bin/jar 2And so on.
Now you can switch between different versions of a Java command as follows:
$ sudo alternatives --config javac
There is 1 program that provides 'javac'.
Selection Command
-----------------------------------------------
*+ 1 /usr/lib/jvm/java-1.8.0-openjdk-1.8.0.101-1.b14.fc23.x86_64/bin/javac
2 /Data/jdk1.8.0_67/bin/javac
Enter to keep the current selection[+], or type selection number: 2
$
For more information on using alternatives, refer to the alternatives(8) manual entry.
Arch based installs
Arch Linux based installs come with the command archlinux-java to switch java versions.
Listing installed environments
$ archlinux-java status
Available Java environments:
java-7-openjdk (default)
java-8-openjdk/jre
Switching current environment
# archlinux-java set <JAVA_ENV_NAME>
Eg:
# archlinux-java set java-8-openjdk/jre
More information can be found on the Arch Linux Wiki
