Converts files from native encodings to ASCII with escaped Unicode. A common usage is to convert source files maintained in a native operating system encoding, to ASCII prior to compilation.

Files in the directory src are converted from a native encoding to ASCII. By default, all files in the directory are converted. However, conversion may be limited to selected files using includes and excludes attributes. For more information on file matching patterns, see the section on directory based tasks. If no encoding is specified, the default encoding for the JVM is used. If ext is specified, then output files are renamed to use it as a new extension. More sophisticated file name translations can be achieved using a nested <mapper> element. By default an identity mapper will be used. If dest and src point to the same directory, the ext attribute or a nested <mapper> is required.

This task forms an implicit FileSet, and supports most attributes of <fileset> (dir becomes src) as well as nested <include>, <exclude>, and <patternset> elements.

It is possible to use different converters. This can be selected with the implementation attribute or a nested element. Here are the choices of the attribute:

Attribute Description Required
reverse Reverse the sense of the conversion, i.e. convert from ASCII to native
Only supported by the sun and builtin converters
encoding The native encoding the files are in No; defaults to default JVM character encoding
src The directory to find files in; default is basedir No
dest The directory to output file to Yes
ext File extension to use in renaming output files No
includes Comma- or space-separated list of patterns of files that must be included. No; defaults to all (**)
includesfile Name of a file. Each line of this file is taken to be an include pattern No
excludes Comma- or space-separated list of patterns of files that must be excluded. No; defaults to default excludes or none if defaultexcludes is no
excludesfile Name of a file. Each line of this file is taken to be an exclude pattern No
defaultexcludes Indicates whether default excludes should be used or not (yes|no). No; defaults to yes
implementation The converter implementation to use. (See the above list of valid converters.) No; defaults to default converter for the current JVM

Parameters specified as nested elements


You can specify additional command line arguments for the converter with nested <arg> elements. These elements are specified like Command-line Arguments but have an additional attribute that can be used to enable arguments only if a given converter implementation will be used.

Attribute Description Required
value See Command-line Arguments. Exactly one of these
implementation Only pass the specified argument if the chosen converter implementation matches the value of this attribute. Legal values are the same as those in the above list of valid compilers.) No


Since Apache Ant 1.8.0

A path-like structure holding the classpath to use when loading the converter implementation if a custom class has been specified. Doesn't have any effect when using one of the built-in converters.

Any nested element of a type that implements Native2AsciiAdapter

Since Ant 1.8.0

If a defined type implements the Native2AsciiAdapter interface a nested element of that type can be used as an alternative to the implementation attribute.


Convert all files in the directory srcdir ending in .eucjis from the EUCJIS encoding to ASCII and rename them to end in .java.

<native2ascii encoding="EUCJIS" src="srcdir" dest="srcdir"
              includes="**/*.eucjis" ext=".java"/>

Convert all the files ending in .java in the directory native/japanese to ASCII, placing the results in the directory src. The names of the files remain the same.

<native2ascii encoding="EUCJIS" src="native/japanese" dest="src"

If you want to use a custom Native2AsciiAdapter org.example.MyAdapter you can either use the implementation attribute:

<native2ascii encoding="EUCJIS" src="srcdir" dest="srcdir"
              includes="**/*.eucjis" ext=".java"

or a define a type and nest this into the task like in:

<componentdef classname="org.example.MyAdapter"
<native2ascii encoding="EUCJIS" src="srcdir" dest="srcdir"
              includes="**/*.eucjis" ext=".java">

in which case your native2ascii adapter can support attributes and nested elements of its own.