java设计模式之适配器模式，大丈夫能屈能伸

/**
 * 目标（Target）接口
 */
public interface Targetable {
 public int v5();
}

/**
 * 适配者（Adaptee）类
 */
public class Adaptee {
 public int v220(){
 return 220;
 }
}

/**
 *
 * 采用对象聚合的方式进行适配
 *
 * 对象的适配器模式
 *
 */
public class ObjectAdapterMode implements Targetable {
 private Adaptee adaptee;
 public ObjectAdapterMode(Adaptee adaptee) {
 this.adaptee = adaptee;
 }
 public int v5() {
 return adaptee.v220()/44;
 }
}

public class ClassAdapterMode extends Adaptee implements Targetable {
 public int v5() {
 return super.v220() / 44;
 }
}

public interface Adapteeable {
 public int v220();
}
public class InterfaceAdapterMode implements Targetable ,Adapteeable{
 public int v220() {
 return 220;
 }
 public int v5() {
 return v220()/44;
 }
}

public class InputStreamReader extends Reader {
 private final StreamDecoder sd;
 /**
 * Creates an InputStreamReader that uses the default charset.
 *
 * @param in An InputStream
 */
 public InputStreamReader(InputStream in) {
 super(in);
 try {
 sd = StreamDecoder.forInputStreamReader(in, this, (String)null); // ## check lock object
 } catch (UnsupportedEncodingException e) {
 // The default encoding should always be available
 throw new Error(e);
 }
 }
 /**
 * Creates an InputStreamReader that uses the named charset.
 *
 * @param in
 * An InputStream
 *
 * @param charsetName
 * The name of a supported
 * {@link java.nio.charset.Charset charset}
 *
 * @exception UnsupportedEncodingException
 * If the named charset is not supported
 */
 public InputStreamReader(InputStream in, String charsetName)
 throws UnsupportedEncodingException
 {
 super(in);
 if (charsetName == null)
 throw new NullPointerException("charsetName");
 sd = StreamDecoder.forInputStreamReader(in, this, charsetName);
 }
 /**
 * Creates an InputStreamReader that uses the given charset.
 *
 * @param in An InputStream
 * @param cs A charset
 *
 * @since 1.4
 * @spec JSR-51
 */
 public InputStreamReader(InputStream in, Charset cs) {
 super(in);
 if (cs == null)
 throw new NullPointerException("charset");
 sd = StreamDecoder.forInputStreamReader(in, this, cs);
 }
 /**
 * Creates an InputStreamReader that uses the given charset decoder.
 *
 * @param in An InputStream
 * @param dec A charset decoder
 *
 * @since 1.4
 * @spec JSR-51
 */
 public InputStreamReader(InputStream in, CharsetDecoder dec) {
 super(in);
 if (dec == null)
 throw new NullPointerException("charset decoder");
 sd = StreamDecoder.forInputStreamReader(in, this, dec);
 }
 /**
 * Returns the name of the character encoding being used by this stream.
 *
 * <p> If the encoding has an historical name then that name is returned;
 * otherwise the encoding's canonical name is returned.
 *
 * <p> If this instance was created with the {@link
 * #InputStreamReader(InputStream, String)} constructor then the returned
 * name, being unique for the encoding, may differ from the name passed to
 * the constructor. This method will return <code>null</code> if the
 * stream has been closed.
 * </p>
 * @return The historical name of this encoding, or
 * <code>null</code> if the stream has been closed
 *
 * @see java.nio.charset.Charset
 *
 * @revised 1.4
 * @spec JSR-51
 */
 public String getEncoding() {
 return sd.getEncoding();
 }
 /**
 * Reads a single character.
 *
 * @return The character read, or -1 if the end of the stream has been
 * reached
 *
 * @exception IOException If an I/O error occurs
 */
 public int read() throws IOException {
 return sd.read();
 }
 /**
 * Reads characters into a portion of an array.
 *
 * @param cbuf Destination buffer
 * @param offset Offset at which to start storing characters
 * @param length Maximum number of characters to read
 *
 * @return The number of characters read, or -1 if the end of the
 * stream has been reached
 *
 * @exception IOException If an I/O error occurs
 */
 public int read(char cbuf[], int offset, int length) throws IOException {
 return sd.read(cbuf, offset, length);
 }
 /**
 * Tells whether this stream is ready to be read. An InputStreamReader is
 * ready if its input buffer is not empty, or if bytes are available to be
 * read from the underlying byte stream.
 *
 * @exception IOException If an I/O error occurs
 */
 public boolean ready() throws IOException {
 return sd.ready();
 }
 public void close() throws IOException {
 sd.close();
 }
}