Appendable (Java Platform SE 8 ) (original) (raw)

• 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

  All Methods Instance Methods Abstract Methods

  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 thisAppendable.

• • Method Detail

     * #### append  
     [Appendable](../../java/lang/Appendable.html "interface in java.lang") append([CharSequence](../../java/lang/CharSequence.html "interface in java.lang") csq)  
                throws [IOException](../../java/io/IOException.html "class in java.io")  
     Appends the specified character sequence to this  
     Appendable  
     .  
      Depending on which class implements the character sequencecsq, the entire sequence may not be appended. For instance, if csq is a [CharBuffer](../../java/nio/CharBuffer.html "class in java.nio") then the subsequence to append is defined by the buffer's position and limit.  
     Parameters:  
     `csq` \- The character sequence to append. If csq isnull, then the four characters "null" are appended to this Appendable.  
     Returns:  
     A reference to this Appendable  
     Throws:  
     `[IOException](../../java/io/IOException.html "class in java.io")` \- If an I/O error occurs  
     * #### append  
     [Appendable](../../java/lang/Appendable.html "interface in java.lang") append([CharSequence](../../java/lang/CharSequence.html "interface in java.lang") csq,  
                       int start,  
                       int end)  
                throws [IOException](../../java/io/IOException.html "class in java.io")  
     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](../../java/lang/IndexOutOfBoundsException.html "class in java.lang")` \- If start or end are negative, start is greater than end, or end is greater thancsq.length()  
     `[IOException](../../java/io/IOException.html "class in java.io")` \- If an I/O error occurs  
     * #### append  
     [Appendable](../../java/lang/Appendable.html "interface in java.lang") append(char c)  
                throws [IOException](../../java/io/IOException.html "class in java.io")  
     Appends the specified character to this  
     Appendable  
     .  
     Parameters:  
     `c` \- The character to append  
     Returns:  
     A reference to this Appendable  
     Throws:  
     `[IOException](../../java/io/IOException.html "class in java.io")` \- If an I/O error occurs

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