Try block:
- Try block has the main code, which code may throw an exception.
a try block syntax looks like the following:
try {
//main code
}
Catch block:
- The catch block contains exception code that is executed when thrown by the Try Block.
- Possible to declare one or more catch block for different type of exception
- No code can be between try block and the first catch block.
- Catch blocks declare directly after the try block.
a catch block syntax looks like the following:
try {
} catch (ExceptionType1 name) {
//exception code
} catch (ExceptionType2 name) {
//exception code
}
Finally, block:
- The finally block always executes after try block or catch block.
- finally block is a block that is used to execute clean up code such as streaming or closing connection, etc.
- Declare cleanup code in a finally block is always a best practice in Java, even when no exceptions have occurred.
a finally block syntax looks like the following:
try {
} catch (ExceptionType1 name) {
//exception code
} catch (ExceptionType2 name) {
//exception code
}
finally {
if (out != null) {
// Close Out - Clean Up Code
} else {
// No need to close Out
}
}
General Syntax
try{
//Do Something
}catch(Exception e){
//Do something with caught exception
}finally{
//Do something always - even when there is an exception
}
Try-Catch-Finally Example Program
public class TryCatchFinally {
static void splitString(String text){
try{
String[] splittedString =text.split("/");
for(int i = 0; i < splittedString.length; i++){
System.out.println("Splitted string array of index "+i+" is : "+splittedString[i]);
}
}
catch(Exception e){
System.out.println("Exception while performing division : "+e.toString());
}
finally{
System.out.println("I am inside finally block");
}
}
public static void main(String args[]){
Scanner scanner = new Scanner(System.in);
System.out.println("Enter number 1 : ");
String text = scanner.nextLine();
if(text.length()>0){
splitString(text);
}else{
//Passing null as input for splitting
splitString(null);
}
}
}
Sample Output 1
Enter the input text :
Exception while performing division : java.lang.NullPointerException
I am inside finally block
Sample Output 2
Enter the input text :
tea/cup
Splitted string array of index 0 is : tea
Splitted string array of index 1 is : cup
I am inside finally block
