JDK= JRE + Development Tools.
JRE= JVM + Library Classes.
- JDK( JAVA Development Kit): It is a software development environment which is used to develop java applications and applets.
-Development Tools:
- Basic Tools (appletviewer, extcheck, jar, java, javac, javadoc, javah, javap, jdb, jdeps)
- Security Tools (keytool, jarsigner, policytool, kinit, klist, ktab)
- Internationalization Tools (native2ascii)
2. JRE(JAVA Runtime Environment):It is the most common environment available on devices to run java programs.
-Library Classes includes:
- Technologies which get used for deployment such as Java Web Start.
- Integration libraries like Java Database Connectivity (JDBC) and Java Naming and Directory Interface (JNDI).
- Libraries such as Lang and util.
- Other base libraries like Java Management Extensions (JMX), Java Native Interface (JNI) and Java for XML Processing (JAX-WS).
3. JVM(JAVA Virtual Machine):It is a specification that provides runtime environment in which java bytecode can be executed. It is platform dependant.
- Loads code
- Verifies code
- Executes code
- Provides runtime environment
click here to know JVM in more details.
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