Interface Appendable

All Known Implementing Classes:: BufferedWriter, CharArrayWriter, CharBuffer, FileWriter, FilterWriter, LogStream, OutputStreamWriter, PipedWriter, PrintStream, PrintWriter, StringBuffer, StringBuilder, StringWriter, Writer

public interface 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 Formatter.

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

Since this interface may be implemented by existing classes with different styles of error handling there is no guarantee that errors will be propagated to the invoker.

Since:: 1.5

Method Summary

Modifier and Type	Method	Description
`Appendable`	`append(char c)`	Appends the specified character to this `Appendable`.
`Appendable`	`append(CharSequence csq)`	Appends the specified character sequence to this `Appendable`.
`Appendable`	`append(CharSequence csq, int start, int end)`	Appends a subsequence of the specified character sequence to this `Appendable`.

Method Details

append

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. For instance, if csq is a CharBuffer then the subsequence to append is defined by the buffer's position and limit.

The contents of this Appendable are unspecified if the CharSequence is modified during the method call or an exception is thrown when accessing the CharSequence.

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:: IOException - If an I/O error occurs

append

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

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

An invocation of this method of the form out.append(csq, start, end) when csq is not null, behaves in exactly the same way as the invocation

    out.append(csq.subSequence(start, end))

The contents of this Appendable are unspecified if the CharSequence is modified during the method call or an exception is thrown when accessing the CharSequence.

Parameters:: 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".; start - The index of the first character in the subsequence; end - The index of the character following the last character in the subsequence
Returns:: A reference to this Appendable
Throws:: IndexOutOfBoundsException - If start or end are negative, start is greater than end, or end is greater than csq.length(); IOException - If an I/O error occurs

append

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:: IOException - If an I/O error occurs

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