Appendable in Java

java.lang.Appendable

An object to which char sequences and values can be appended. The Appendable interface must be implemented by any class whose instances are intended to receive formatted output from a java.util.Formatter.

The characters to be appended should be valid Unicode characters as described in Unicode CharacterRepresentation.

Note that supplementary characters may be composed of multiple 16-bit char values.

Appendables are not necessarily safe for multithreaded access. Thread safety is the responsibility of classes that extend and implement this interface.

Implementing Classes:

BufferedWriter

CharArrayWriter

CharBuffer

FileWriter

FilterWriter

LogStream

OutputStreamWriter

PipedWriter

PrintStream

PrintWriter

StringBuffer

StringBuilder

StringWriter

Writer

Declaration

public interface Appendable {

    Appendable append(CharSequence csq) throws IOException;

    Appendable append(CharSequence csq, int start, int end) throws IOException;

    Appendable append(char c) throws IOException;
}

Methods

1. Appendable.append(CharSequence csq)

Appendable java.lang.Appendable.append(CharSequence csq) throws IOException

Appends the specified character sequence to this Appendable.

Depending on which class implements the character sequence csq, the entire sequence may not be appended.

Parameters: csq The character sequence to append. If csq is null, then the four characters "null" are appended to this Appendable.

Returns: A reference to this Appendable.

Throws:

1. IOException - If an I/O error occurs

2. Appendable.append(CharSequence csq, int start, int end)

Appendable java.lang.Appendable.append(CharSequence csq, int start, int end) throws IOException

Appends a subsequence of the specified character sequence to this Appendable.

Parameters:

1. csq The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null".

2. start The index of the first character in the subsequence.

3. end The index of the character following the last character in the subsequence.

Returns: A reference to this Appendable.

Throws:

1. IndexOutOfBoundsException - If start or end is negative, start is greater than end, or end is greater than csq.length()

2. IOException - If an I/O error occurs.

3. Appendable.append(char c)

Appendable java.lang.Appendable.append(char c) throws IOException

Appends the specified character to this Appendable.

Parameters: c The character to append.

Returns: A reference to this Appendable.

Throws:

1. IOException - If an I/O error occurs