Java Character Stream

Tags:

• Java

Character Stream

Among the classes in the java.io package, character stream-related classes are as follows.

• Reader
  • BufferedReader
  • InputStreamReader
    • FileReader
• Writer
  • BufferedWriter
  • OutputStreamWriter
    • FileWriter

Reader/Writer Abstract Classes

Because the Writer and Reader classes are abstract classes, actual objects cannot be created from them.

Reader Abstract Class

The Reader class provides character stream input functionality.

Main Reader Methods

Method	Description
abstract void close() throws IOException	Closes the character input stream.
void mark(int limit) throws IOException	Marks the current position of the character input stream.
boolean markSupported()	Returns whether the character stream supports the mark() method.
int read() throws IOException	Reads a single character from the character input stream.
int read(char buf[]) throws IOException	Reads up to the size of buf[] from the character input stream, stores it in buf, and returns the number of characters read.
abstract int read(char buf[], int off, int len) throws IOException	Reads len characters from the character input stream, stores them at off in buf[], and returns the number of characters read.
int read(CharBuffer target) throws IOException	Reads a string into target, which is a CharBuffer.
boolean ready() throws IOException	Returns whether the character input stream is ready.
void reset() throws IOException	Returns the character input stream to the marked position.
long skip(long l) throws IOException	Skips the given number l of characters.

Writer Abstract Class

The Writer class provides character stream output functionality.

Main Writer Methods

Method	Description
Writer append(char c) throws IOException	Adds Character c to the Writer.
Writer append(CharSequence csq) throws IOException	Adds CharSequence csq to the Writer.
Writer append(CharSequence csq, int start, int end) throws IOException	Adds characters from start to end of CharSequence csq to the Writer.
abstract void close() throws IOException	Closes the character output stream.
abstract void flush() throws IOException	Outputs the remaining output stream in the buffer.
void write(String str) throws IOException	Outputs the given string str.
void write(char buf[]) throws IOException	Outputs the contents of buf.
void write(char buf[], int off, int len) throws IOException	Outputs len characters from the off position of buf.
void write(String str, int off, int len) throws IOException	Outputs len characters from the off position in the given string str.