javax.activation: public class: FileDataSource

javax.activation
public class: FileDataSource [javadoc | source]

java.lang.Object
   javax.activation.FileDataSource

All Implemented Interfaces:
DataSource

The FileDataSource class implements a simple DataSource object that encapsulates a file. It provides data typing services via a FileTypeMap object.

FileDataSource Typing Semantics

The FileDataSource class delegates data typing of files to an object subclassed from the FileTypeMap class. The setFileTypeMap method can be used to explicitly set the FileTypeMap for an instance of FileDataSource. If no FileTypeMap is set, the FileDataSource will call the FileTypeMap's getDefaultFileTypeMap method to get the System's default FileTypeMap.

Also see:

javax.activation.DataSource

javax.activation.FileTypeMap

javax.activation.MimetypesFileTypeMap

since: 1.6 -

Constructor:

Constructor:
public FileDataSource(File file) { _file = file; // save the file Object... } Creates a FileDataSource from a File object. Note: The file will not actually be opened until a method is called that requires the file to be opened. Parameters: `file` - the file
public FileDataSource(String name) { this(new File(name)); // use the file constructor } Creates a FileDataSource from the specified path name. Note: The file will not actually be opened until a method is called that requires the file to be opened. Parameters: `name` - the system-dependent file name.

 public FileDataSource(File file) {
        _file = file;   // save the file Object...
}

Note: The file will not actually be opened until a method is called that requires the file to be opened.

Parameters:

file - the file

 public FileDataSource(String name) {
        this(new File(name));   // use the file constructor
}

Note: The file will not actually be opened until a method is called that requires the file to be opened.

Parameters:

name - the system-dependent file name.

Method from javax.activation.FileDataSource Summary:
getContentType, getFile, getInputStream, getName, getOutputStream, setFileTypeMap

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from javax.activation.FileDataSource Detail:
public String getContentType() { // check to see if the type map is null? if (typeMap == null) return FileTypeMap.getDefaultFileTypeMap().getContentType(_file); else return typeMap.getContentType(_file); } This method returns the MIME type of the data in the form of a string. This method uses the currently installed FileTypeMap. If there is no FileTypeMap explictly set, the FileDataSource will call the `getDefaultFileTypeMap` method on FileTypeMap to acquire a default FileTypeMap. Note: By default, the FileTypeMap used will be a MimetypesFileTypeMap.
public File getFile() { return _file; } Return the File object that corresponds to this FileDataSource.
public InputStream getInputStream() throws IOException { return new FileInputStream(_file); } This method will return an InputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of InputStream with each invocation.
public String getName() { return _file.getName(); } Return the name of this object. The FileDataSource will return the file name of the object.
public OutputStream getOutputStream() throws IOException { return new FileOutputStream(_file); } This method will return an OutputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of OutputStream with each invocation.
public void setFileTypeMap(FileTypeMap map) { typeMap = map; } Set the FileTypeMap to use with this FileDataSource

Method from javax.activation.FileDataSource Detail:

 public String getContentType() {
        // check to see if the type map is null?
        if (typeMap == null)
            return FileTypeMap.getDefaultFileTypeMap().getContentType(_file);
        else
            return typeMap.getContentType(_file);
}

getDefaultFileTypeMap

Note: By default, the FileTypeMap used will be a MimetypesFileTypeMap.

 public File getFile() {
        return _file;
}

Return the File object that corresponds to this FileDataSource.

 public InputStream getInputStream() throws IOException {
        return new FileInputStream(_file);
}

This method will return an InputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of InputStream with each invocation.

 public String getName() {
        return _file.getName();
}

name

 public OutputStream getOutputStream() throws IOException {
        return new FileOutputStream(_file);
}

This method will return an OutputStream representing the the data and will throw an IOException if it can not do so. This method will return a new instance of OutputStream with each invocation.

 public  void setFileTypeMap(FileTypeMap map) {
        typeMap = map;
}

Set the FileTypeMap to use with this FileDataSource