Why we use inputstream in java

Notice how the while loop continues until a -1 value is read from the InputStream read method. After that, the while loop exits, and the InputStream close method is called. If an exception is thrown while reading data from the InputStream , the close method is never called. To make the code more robust, you will have to use the Java try-with-resources construct. Here is an example of closing a Java InputStream using the try-with-resources construct:.

Notice how the InputStream is now declared inside the parentheses after the try keyword. This signals to Java that this InputStream is to be managed by the try-with-resources construct. Once the executing thread exits the try block, the inputstream variable is closed.

If an exception is thrown from inside the try block, the exception is caught, the InputStream is closed, and then the exception is rethrown. You are thus guaranteed that the InputStream is closed, when used inside a try-with-resources block. The Java InputStream is a byte based stream of data.

You can read more about how to use the InputStreamReader by clicking the link in the previous sentence, but here is a quick example of converting an InputStream to an InputStreamReader :. Tutorials About RSS. Java IO. End of Stream If the read method returns -1, the end of stream has been reached, meaning there is no more data to read in the InputStream.

When the end of stream has been reached, you can close the InputStream. These methods are: int read byte[] int read byte[], int offset, int length The read byte[] method will attempt to read as many bytes into the byte array given as parameter as the array has space for.

Tweet Jakob Jenkov. Featured Videos Sponsored Ads. All Trails. Trail TOC. In order to create an InputStream, we must import the java. InputStream package first. Once we import the package, here is how we can create the input stream. Here, we have created an input stream using FileInputStream. It is because InputStream is an abstract class. Hence we cannot create an object of InputStream. Note : We can also create an input stream from other subclasses of InputStream.

The InputStream class provides different methods that are implemented by its subclasses. Here are some of the commonly used methods:. In the above example, we have created an input stream using the FileInputStream class. The input stream is linked with the file input. Bohemian Bohemian 5, 11 11 gold badges 37 37 silver badges 47 47 bronze badges. Add a comment. Active Oldest Votes. InputStream is used for many things that you read from. OutputStream is used for many things that you write to.

Improve this answer. Chip Uni Chip Uni 7, 1 1 gold badge 21 21 silver badges 28 28 bronze badges. KorayTugay A stream is generally defined as a set of characters.

To be more precise, more than one bit or character is called as a stream. More than one character is String also. What differentiates stream from string? I think a stream is just zeros and ones. PrajeetShrestha I think a stream also has the implication that data the data is available sequentially no random access and not persistent can't re-read or modify written data.

The data may also not be available when requested. Stream data means the data is represented in binary format. Show 1 more comment. Arne Deutsch Arne Deutsch From the Java Tutorial : A stream is a sequence of data. A program uses an input stream to read data from a source, one item at a time: A program uses an output stream to write data to a destination, one item at time: The data source and data destination pictured above can be anything that holds, generates, or consumes data.

Sample code from oracle tutorial: import java. FileInputStream; import java. FileOutputStream; import java. Ravindra babu Ravindra babu Kaleb Brasee Kaleb Brasee A stream is a continuous flow of liquid, air, or gas. Jan Bodnar Jan Bodnar 8, 5 5 gold badges 56 56 silver badges 65 65 bronze badges.

Community Bot 1 1 1 silver badge. The data are streaming from the source into the program. Computed results are streaming from the program to the destination.

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