org.apache.commons.io.output

Class ProxyCollectionWriter

  • All Implemented Interfaces:
    Closeable, Flushable, Appendable, AutoCloseable
    Direct Known Subclasses:
    TeeWriter

    public class ProxyCollectionWriter
    extends FilterCollectionWriter
    A Proxy stream collection which acts as expected, that is it passes the method calls on to the proxied streams and doesn't change which methods are being called. It is an alternative base class to FilterWriter and FilterCollectionWriter to increase reusability, because FilterWriter changes the methods being called, such as write(char[]) to write(char[], int, int) and write(String) to write(String, int, int). This is in contrast to ProxyWriter which is backed by a single Writer.
    Since:
    2.7
    • Constructor Detail

      • ProxyCollectionWriter

        public ProxyCollectionWriter(Collection<Writer> writers)
        Creates a new proxy collection writer.
        Parameters:
        writers - Writers object to provide the underlying targets.
      • ProxyCollectionWriter

        public ProxyCollectionWriter(Writer... writers)
        Creates a new proxy collection writer.
        Parameters:
        writers - Writers to provide the underlying targets.
    • Method Detail

      • afterWrite

        protected void afterWrite(int n)
                           throws IOException
        Invoked by the write methods after the proxied call has returned successfully. The number of chars written (1 for the write(int) method, buffer length for write(char[]), etc.) is given as an argument.

        Subclasses can override this method to add common post-processing functionality without having to override all the write methods. The default implementation does nothing.

        Parameters:
        n - number of chars written
        Throws:
        IOException - if the post-processing fails
      • append

        public Writer append(CharSequence csq,
                             int start,
                             int end)
                      throws IOException
        Invokes the delegates' append(CharSequence, int, int) methods.
        Specified by:
        append in interface  Appendable
        Overrides:
        append in class  FilterCollectionWriter
        Parameters:
        csq - The character sequence to write
        start - The index of the first character to write
        end - The index of the first character to write (exclusive)
        Returns:
        this writer
        Throws:
        IOException - if an I/O error occurs.
      • beforeWrite

        protected void beforeWrite(int n)
                            throws IOException
        Invoked by the write methods before the call is proxied. The number of chars to be written (1 for the write(int) method, buffer length for write(char[]), etc.) is given as an argument.

        Subclasses can override this method to add common pre-processing functionality without having to override all the write methods. The default implementation does nothing.

        Parameters:
        n - number of chars to be written
        Throws:
        IOException - if the pre-processing fails
      • handleIOException

        protected void handleIOException(IOException e)
                                  throws IOException
        Handle any IOExceptions thrown.

        This method provides a point to implement custom exception handling. The default behavior is to re-throw the exception.

        Parameters:
        e - The IOException thrown
        Throws:
        IOException - if an I/O error occurs.
      • write

        public void write(char[] cbuf)
                   throws IOException
        Invokes the delegate's write(char[]) method.
        Overrides:
        write in class  FilterCollectionWriter
        Parameters:
        cbuf - the characters to write
        Throws:
        IOException - if an I/O error occurs.
      • write

        public void write(char[] cbuf,
                          int off,
                          int len)
                   throws IOException
        Invokes the delegate's write(char[], int, int) method.
        Overrides:
        write in class  FilterCollectionWriter
        Parameters:
        cbuf - the characters to write
        off - The start offset
        len - The number of characters to write
        Throws:
        IOException - if an I/O error occurs.
      • write

        public void write(String str,
                          int off,
                          int len)
                   throws IOException
        Invokes the delegate's write(String) method.
        Overrides:
        write in class  FilterCollectionWriter
        Parameters:
        str - the string to write
        off - The start offset
        len - The number of characters to write
        Throws:
        IOException - if an I/O error occurs.

Copyright © 2002–2021 The Apache Software Foundation. All rights reserved.