*/
package org.opendaylight.yangtools.yang.common;
+import com.google.common.base.MoreObjects;
+import com.google.common.collect.Interner;
+import com.google.common.collect.Interners;
import java.io.Serializable;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Date;
-
+import java.util.Objects;
import org.opendaylight.yangtools.concepts.Immutable;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public final class QNameModule implements Immutable, Serializable {
- private static final Logger LOG = LoggerFactory.getLogger(QNameModule.class);
- private static final long serialVersionUID = 1L;
+ private static final Interner<QNameModule> INTERNER = Interners.newWeakInterner();
+ private static final Logger LOG = LoggerFactory.getLogger(QNameModule.class);
+ private static final QNameModule NULL_INSTANCE = new QNameModule(null, null);
+ private static final long serialVersionUID = 2L;
//Nullable
private final URI namespace;
private final Date revision;
//Nullable
- private final String formattedRevision;
+ private transient volatile String formattedRevision;
+
+ private transient int hash;
private QNameModule(final URI namespace, final Date revision) {
this.namespace = namespace;
this.revision = revision;
- if(revision != null) {
- this.formattedRevision = SimpleDateFormatUtil.getRevisionFormat().format(revision);
- } else {
- this.formattedRevision = null;
+ }
+
+ /**
+ * Return an interned reference to a equivalent QNameModule.
+ *
+ * @return Interned reference, or this object if it was interned.
+ */
+ public QNameModule intern() {
+ return INTERNER.intern(this);
+ }
+
+ /**
+ * Create a new QName module instance with specified namespace/revision.
+ *
+ * @param namespace Module namespace
+ * @param revision Module revision
+ * @return A new, potentially shared, QNameModule instance
+ */
+ public static QNameModule create(final URI namespace, final Date revision) {
+ if (namespace == null && revision == null) {
+ return NULL_INSTANCE;
}
+
+ return new QNameModule(namespace, revision);
}
- public static QNameModule create(final URI namespace, final Date revision) {
- return new QNameModule(namespace, revision);
- }
+ public String getFormattedRevision() {
+ if (revision == null) {
+ return null;
+ }
- public String getFormattedRevision() {
- return formattedRevision;
- }
+ String ret = formattedRevision;
+ if (ret == null) {
+ ret = SimpleDateFormatUtil.getRevisionFormat().format(revision);
+ formattedRevision = ret;
+ }
- public URI getNamespace() {
- return namespace;
- }
+ return ret;
+ }
- public Date getRevision() {
- return revision;
- }
+ /**
+ * Returns the namespace of the module which is specified as argument of
+ * YANG Module <b><font color="#00FF00">namespace</font></b> keyword.
+ *
+ * @return URI format of the namespace of the module
+ */
+ public URI getNamespace() {
+ return namespace;
+ }
+
+ /**
+ * Returns the revision date for the module.
+ *
+ * @return date of the module revision which is specified as argument of
+ * YANG Module <b><font color="#339900">revison</font></b> keyword
+ */
+ public Date getRevision() {
+ return revision;
+ }
@Override
public int hashCode() {
- final int prime = 31;
- int result = (namespace == null) ? 0 : namespace.hashCode();
- result = prime * result + ((formattedRevision == null) ? 0 : formattedRevision.hashCode());
- return result;
+ if (hash == 0) {
+ hash = Objects.hash(namespace, revision);
+ }
+ return hash;
}
@Override
return false;
}
final QNameModule other = (QNameModule) obj;
- if (namespace == null) {
- if (other.namespace != null) {
- return false;
- }
- } else if (!namespace.equals(other.namespace)) {
- return false;
- }
- if (formattedRevision == null) {
- if (other.formattedRevision != null) {
- return false;
- }
- } else if (!revision.equals(other.revision)) {
- return false;
- }
- return true;
+ return Objects.equals(revision, other.revision) && Objects.equals(namespace, other.namespace);
}
/**
*
*/
URI getRevisionNamespace() {
-
if (namespace == null) {
return null;
}
- String query = "";
- if (revision != null) {
- query = "revision=" + formattedRevision;
- }
-
- URI compositeURI = null;
+ final String query = revision == null ? "" : "revision=" + getFormattedRevision();
try {
- compositeURI = new URI(namespace.getScheme(), namespace.getUserInfo(), namespace.getHost(),
+ return new URI(namespace.getScheme(), namespace.getUserInfo(), namespace.getHost(),
namespace.getPort(), namespace.getPath(), query, namespace.getFragment());
- } catch (URISyntaxException e) {
- LOG.error("", e);
+ } catch (final URISyntaxException e) {
+ LOG.error("Failed to construct URI for {}", this, e);
+ return null;
}
- return compositeURI;
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(QNameModule.class).omitNullValues().add("ns", getNamespace()).add("rev", getFormattedRevision()).toString();
}
}