JDK 7 features

Java Development Kit (JDK) 7 is most recent release of Java Standard Platform. I takes the birth at the OpenJDK project and has taken collaborative effort of Sun and Java developer community.

JVM

• Extensions to the JVM  to support the implementation of dynamically-typed languages (InvokeDynamic) at performance levels near to that of the Java language itself. 

Programming Language

• The integral types (byte, short, int, and long) can also be expressed using the binary number system. To specify a binary literal, add the prefix 0b or 0B to the number.
• The String class can be used in the expression of a switch statement.
• A single catch block can handle more than one type of exception. In addition, the compiler performs more precise analysis of rethrown exceptions than earlier releases of Java SE.
• The try-with-resources statement ensures that each resource is closed at the end of the statement. Any object that implements the new java.lang.AutoCloseable interface or the java.io.Closeable interface can be used as a resource. 
• The type arguments required to invoke the constructor of a generic class can be replaced with an empty set of type parameters (<>) as long as the compiler can infer the type arguments from the context.
• The Java SE 7 complier generates a warning at the declaration site of a varargs method or constructor with a non-reifiable varargs formal parameter.

  

Networking 

• The URLClassLoader.close() method effectively eliminates the problem of how to support updated implementations of the classes and resources loaded from a particular codebase, and in particular from JAR files.
• Sockets Direct Protocol support for reliable, high-performance network streams over Infiniband connections on Solaris and Linux.

Concurrency Utilities

• The fork/join framework is designed to efficiently run a large number of tasks using a pool of worker threads.
• The ThreadLocalRandom class eliminates contention among threads using pseudo-random numbers.
• The Phaser class is a new synchronization barrier.

I/O

• New APIs for filesystem access, scalable asynchronous I/O operations, socket-channel binding and configuration, and multicast datagrams.
• A fully-functional and supported NIO.2 filesystem provider for zip and jar files.

JDBC

• The ability to use a try-with-resources statement to automatically close resources of type Connection, ResultSet, and Statement.
• RowSet 1.1: The introduction of the RowSetFactory interface and the RowSetProvider class, which enable you to create all types of row sets supported by your JDBC driver.