BufferedReader >
- BufferedReader is buffered.
- BufferedReader reads characters from another Reader (Eg - FileReader)
- when BufferedReader.read() is called mostly data is read from the buffer. When data is not available available in buffer a call is made to read system file and lot of characters are kept in buffer.
- A BufferedReader enables another Reader to buffer the characters and supports the mark and reset methods.
- BufferedReader is much faster as compared to FileReader.
- Example -
- As we discussed above that when BufferedReader.read() is called mostly data is read from the buffer.
- A BufferedReader reads from FileReader, will request lot of data from the FileReader (128 characters or so… not exact figure). Thus only 2 calls will be made for reading 256 characters from file.
- Another Example - Real world Example - You must have seen youtube videos where video is buffered before you actually start watching it, buffering overall improves your video watching experience.
We will read c:/myFile.txt
c:/myFile.txt looks like this >
You are learning File IO from javaMadeSoEasy.com
|
In this post we’ll write >
- Program 1 to Read text from file using BufferedReader's read() method in java file IO
- Program 2 to Read text from file using BufferedReader's readLine() method in java file IO
Program 1 to Read text from file using BufferedReader's read() method in java file IO
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
/** JavaMadeSoEasy.com */
public class ReadFileUsingFileReader {
public static void main(String... args) {
FileReader fr = null;
BufferedReader br = null;
try {
fr = new FileReader("c:/myFile.txt");
br = new BufferedReader(fr);
System.out.println("Reading from text file using "
+ "BufferedReader's read() method > ");
int ch;
while ((ch = br.read()) != -1) { //read till end of file
System.out.print((char) ch);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (br != null)
br.close(); //close BufferedReader
// will close FileReader
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/* OUTPUT
Reading from text file using BufferedReader's read() method >
You are learning File IO from javaMadeSoEasy.com
*/
|
Program 2 to Read text from file using BufferedReader's readLine() method in java file IO
BufferedReader's readLine() method reads whole line and return it in String form.
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
/** JavaMadeSoEasy.com */
public class ReadFileUsingFileReader {
public static void main(String... args) {
FileReader fr = null;
BufferedReader br = null;
try {
fr = new FileReader("c:/myFile.txt");
br = new BufferedReader(fr);
System.out.println("Reading from text file using "
+ "BufferedReader's readLine() method > ");
String str;
while ((str = br.readLine()) != null) { //read till end of file
System.out.print(str);
}
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (br != null)
br.close(); //close BufferedReader
// will close FileReader
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/* OUTPUT
Reading from text file using BufferedReader's readLine() method >
You are learning File IO from javaMadeSoEasy.com
*/
|
RELATED LINKS>
Program to How to use Mark and Reset methods with BufferedReader
Difference between FileInputStream and BufferedInputStream in java file IO
Copy a file in java 2 in ways - use org.apache.commons.io.FileUtils's copyDirectory(sourceDirectory, destDirectory)
Program to Move a file - in java file IO
Labels:
Core Java
File IO/File handling