Switch and try-with-resources - JDK7

1. Strings with switch statement:-

JDK7 allows you to use strings with switch statement. In this case swicth internally uses equals method. This structure is always better that if-else-if ladder. Here is one simple example,

String numbers = “one”;

Int x = 1000;

switch(numbers) {

                case “one”: x = 1;  break;

                case “two”: x = 2; break;

                case “three”: x = 3; break;

                case “four”: x = 4; break;

                :

                :

                default : System.out.print(“This is wrong option.”);

}

2. try-with-resources statement:-

In this try statement we can declare one or more resources which must be closed after it’s work is finished. Here is one small example,

try(BufferedReader br = new BufferedReader(file)) {

                br.readLine();

}

In this code br will be closed automatically in normal execution as well as exceptional condition onse it is out of try block. Before JDK7 we were using finally block. If exception is occuring then that exception will be suppressed and that object will be closed. You can obtain that suppressed exception using Throwable.getSuppressed method.

Again this feature introduces new interface called AutoClosable.

Catching multiple exceptions:-

This is very simple to understand. JDK7 allows single catch to handle multiple exceptions. This reduces code redundancy. Here is simple exmaple,

try {

                //Some code.

} catch(IOException | SQLException e) {

}