What is a filter in java?
The Java Servlet specification version 2.3 introduces a new component type, called a filter. A filter dynamically intercepts requests and responses to transform or use the information contained in the requests or responses. … Second, filters can be used to transform the response from a servlet or a JSP page.
What are the i/o basics in java?
Java IO : Input-output in Java with Examples
|DataInputStream||It contains method for reading java standard datatypes.|
|FileInputStream||This is used to reads from a file|
|InputStream||This is an abstract class that describes stream input.|
|PrintStream||This contains the most used print() and println() method|
What is meant by io in java?
The Java I/O package, a.k.a. java.io, provides a set of input streams and a set of output streams used to read and write data to files or other input and output sources. There are three categories of classes in java.io: input streams, output streams and everything else.
What are the types of I O streams in java?
Some important Byte stream classes.
|DataOutputStream||An output stream that contain method for writing java standard data type|
|FileInputStream||Input stream that reads from a file|
|FileOutputStream||Output stream that write to a file.|
|InputStream||Abstract class that describe stream input.|
When destroy method of a filter is called?
The destroy() method is called after the filter has executed doFilter method. The destroy() method is called only once at the end of the life cycle of a filter.
What are the 3 file I O classes we use?
There are 3 basic file I/O classes in C++: ifstream (derived from istream), ofstream (derived from ostream), and fstream (derived from iostream). These classes do file input, output, and input/output respectively. To use the file I/O classes, you will need to include the fstream header.
What is URL in Java?
The Java URL class represents an URL. URL is an acronym for Uniform Resource Locator. It points to a resource on the World Wide Web. … A URL contains many information: Protocol: In this case, http is the protocol.
What is Randomaccessfile in Java?
This class is used for reading and writing to random access file. A random access file behaves like a large array of bytes. If end-of-file is reached before the desired number of byte has been read than EOFException is thrown. … It is a type of IOException.
What is i/o exception?
IOException is usually a case in which the user inputs improper data into the program. This could be data types that the program can’t handle or the name of a file that doesn’t exist. When this happens, an exception (IOException) occurs telling the compiler that invalid input or invalid output has occurred.
What is I O stream in Java?
In this tutorial, we will learn about Java input/output streams and their types. In Java, streams are the sequence of data that are read from the source and written to the destination. An input stream is used to read data from the source. And, an output stream is used to write data to the destination.
What are the types of I O streams?
In general, a Stream will be an input stream or, an output stream. InputStream − This is used to read data from a source.
- Standard Input − This is used to read data from user through input devices. …
- Standard Output − This is used to project data (results) to the user through output devices.
Why InputStream is used in Java?
The InputStream is used to read data from a source and the OutputStream is used for writing data to a destination. Here is a hierarchy of classes to deal with Input and Output streams.
What is the use of IO class?
What is the use of IO class? Explanation: The IO class provides functions that can be used to handle input and output operations. All the inputs from standard input and standard output, and also from the files can be handled. This gives the flexibility to make the programs more user friendly.