Module java.base
Package java.lang

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.

      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))

      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