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Java in a Nutshell

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24.21 java.io.FileReader (JDK 1.1)

FileReader is a convenience subclass of InputStreamReader that is useful when you want to read text (as opposed to binary data) from a file. You create a FileReader by specifying the file to be read, in any of three possible forms. The FileReader constructor internally creates a FileInputStream to read bytes from the specified file, and uses the functionality of its superclass, InputStreamReader, to convert those bytes from characters in the local encoding to the Unicode characters used by Java.

Because FileReader is a trivial subclass of InputStreamReader, it does not define any read() methods or other methods of its own. Instead, it inherits all its methods from its superclass.

If you want to read Unicode characters from a file that uses some encoding other than the default encoding for the locale, you must explicitly create your own InputStreamReader to perform the byte-to-character conversion.

public class FileReader extends InputStreamReader {
    // Public Constructors
            public FileReader(String fileName) throws FileNotFoundException;
            public FileReader(File file) throws FileNotFoundException;
            public FileReader(FileDescriptor fd);
}

Hierarchy:

Object->Reader->InputStreamReader->FileReader


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