import com.google.common.base.Optional;
/**
- * Metadata contains information about a source, e.g. the name of the content,
- * the artist performing it, dates, comments, URLs, etc. The {@link Format},
- * however, is not part of the metadata because a {@link Source} already exposes
- * it.
+ * Metadata contains information about a source, e.g. the number of channels,
+ * the frequency, the encoding, the name of the content, the artist performing
+ * it, dates, comments, URLs, etc.
* <p/>
* Metadata, once created, is immutable.
*
*/
public class Metadata {
+ /** Constant for an unknown number of channels. */
+ public static final int UNKNOWN_CHANNELS = -1;
+
+ /** Constant for an unknown frequency. */
+ public static final int UNKNOWN_FREQUENCY = -1;
+
+ /** Constant for an unknown metadata. */
+ public static final String UNKNOWN_ENCODING = "UNKNOWN";
+
+ /** The number of channels of this metadata. */
+ private final int channels;
+
+ /** The sampling frequency of this metadata. */
+ private final int frequency;
+
+ /** The encoding of this metadata. */
+ private final String encoding;
+
/** The artist performing the content. */
private final Optional<String> artist;
private final Optional<String> name;
/** Creates empty metadata. */
- public Metadata() {
- this(null, null);
+ public Metadata(int channels, int frequency, String encoding) {
+ this(channels, frequency, encoding, null, null);
}
/**
* @param name
* The name of the content (may be {@code null})
*/
- private Metadata(String artist, String name) {
+ private Metadata(int channels, int frequency, String encoding, String artist, String name) {
+ this.channels = channels;
+ this.frequency = frequency;
+ this.encoding = encoding;
this.artist = Optional.fromNullable(artist);
this.name = Optional.fromNullable(name);
}
+ //
+ // ACCESSORS
+ //
+
+ /**
+ * Returns the number of channels of this metadata.
+ *
+ * @return The number of channels of this metadata
+ */
+ public int channels() {
+ return channels;
+ }
+
+ /**
+ * Returns a metadata with the same parameters as this metadata and the given
+ * number of channels.
+ *
+ * @param channels
+ * The new number of channels
+ * @return A new metadata with the given number of channels
+ */
+ public Metadata channels(int channels) {
+ return new Metadata(channels, frequency, encoding, artist.orNull(), name.orNull());
+ }
+
+ /**
+ * Returns the sampling frequency of this metadata.
+ *
+ * @return The sampling frequency of this metadata
+ */
+ public int frequency() {
+ return frequency;
+ }
+
+ /**
+ * Returns a new metadata with the same parameters as this metadata and the
+ * given frequency.
+ *
+ * @param frequency
+ * The new frequency
+ * @return A new metadata with the given frequency
+ */
+ public Metadata frequency(int frequency) {
+ return new Metadata(channels, frequency, encoding, artist.orNull(), name.orNull());
+ }
+
+ /**
+ * Returns the encoding of this metadata
+ *
+ * @return The encoding of this metadata
+ */
+ public String encoding() {
+ return encoding;
+ }
+
+ /**
+ * Returns a new metadata with the same parameters as this metadata and the
+ * given encoding.
+ *
+ * @param encoding
+ * The new encoding
+ * @return A new metadata with the given encoding
+ */
+ public Metadata encoding(String encoding) {
+ return new Metadata(channels, frequency, encoding, artist.orNull(), name.orNull());
+ }
+
/**
* Returns the artist, if any.
*
* @return New metadata with a changed artist
*/
public Metadata artist(String artist) {
- return new Metadata(artist, this.artist.orNull());
+ return new Metadata(channels, frequency, encoding, artist, this.artist.orNull());
}
/**
* @return New metadata with a changed name
*/
public Metadata name(String name) {
- return new Metadata(name, this.name.orNull());
+ return new Metadata(channels, frequency, encoding, name, this.name.orNull());
+ }
+
+ //
+ // OBJECT METHODS
+ //
+
+ @Override
+ public int hashCode() {
+ int hashCode = (channels << 16) ^ frequency ^ encoding.toUpperCase().hashCode();
+ if (artist.isPresent()) {
+ hashCode ^= artist.get().hashCode();
+ }
+ if (name.isPresent()) {
+ hashCode ^= name.get().hashCode();
+ }
+ return hashCode;
+ }
+
+ @Override
+ public boolean equals(Object object) {
+ if ((object == null) || (getClass() != object.getClass())) {
+ return false;
+ }
+ Metadata metadata = (Metadata) object;
+ if ((metadata.channels != channels) || (metadata.frequency != frequency) || !metadata.encoding.equalsIgnoreCase(encoding())) {
+ return false;
+ }
+ if (artist.equals(metadata.artist)) {
+ return false;
+ }
+ if (name.equals(metadata.name)) {
+ return false;
+ }
+ return true;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder string = new StringBuilder();
+ string.append(String.format("%d Channel%s, %d Hz, %s:", channels, channels != 1 ? "s" : "", frequency, encoding));
+ if (artist.isPresent()) {
+ string.append(" Artist(").append(artist.get()).append(")");
+ }
+ if (name.isPresent()) {
+ string.append(" Name(").append(name.get()).append(")");
+ }
+ return string.toString();
}
}
projects / sonitus.git / blobdiff