import com.sun.org.apache.xerces.internal.util.EncodingMap; //导入依赖的package包/类
/**
 * Returns a writer for this encoding based on
 * an output stream.
 *
 * @return A suitable writer
 * @exception UnsupportedEncodingException There is no convertor
 *  to support this encoding
 */
public Writer getWriter(OutputStream output)
    throws UnsupportedEncodingException {
    // this should always be true!
    if (javaName != null)
        return new OutputStreamWriter(output, javaName);
    javaName = EncodingMap.getIANA2JavaMapping(ianaName);
    if(javaName == null)
        // use UTF-8 as preferred encoding
        return new OutputStreamWriter(output, "UTF8");
    return new OutputStreamWriter(output, javaName);
}
 

import com.sun.org.apache.xerces.internal.util.EncodingMap; //导入依赖的package包/类
/**
 * Creates new <code>EncodingInfo</code> instance.
 */
public EncodingInfo(String ianaName, String javaName, int lastPrintable) {
    this.ianaName = ianaName;
    this.javaName = EncodingMap.getIANA2JavaMapping(ianaName);
    this.lastPrintable = lastPrintable;
}