QNm.java

package org.basex.query.item;

import static org.basex.query.util.Err.*;
import static org.basex.util.Token.*;

import javax.xml.namespace.QName;
import org.basex.query.QueryContext;
import org.basex.query.QueryException;
import org.basex.query.util.Err;
import org.basex.util.InputInfo;
import org.basex.util.Token;
import org.basex.util.TokenBuilder;
import org.basex.util.Util;

/**
 * QName item.
 *
 * @author BaseX Team 2005-12, BSD License
 * @author Christian Gruen
 */
public final class QNm extends Item {
  /** Namespace URI. */
  private byte[] uri;
  /** Name with optional prefix. */
  private byte[] name;
  /** Prefix index. */
  private int pref;

  /**
   * Empty constructor.
   */
  public QNm() {
    super(AtomType.QNM);
    name = EMPTY;
  }

  /**
   * Constructor.
   * @param n name
   */
  public QNm(final byte[] n) {
    super(AtomType.QNM);
    name = n;
    pref = indexOf(n, ':');
  }

  /**
   * Constructor.
   * @param n name
   * @param u namespace URI
   */
  public QNm(final byte[] n, final byte[] u) {
    this(n);
    uri(u);
  }

  /**
   * Constructor, binding a statically known namespace.
   * If no namespace is found, the namespace uri is set to {@code null}.
   * @param n name
   * @param ctx query context
   */
  public QNm(final byte[] n, final QueryContext ctx) {
    this(n);
    uri(ctx.sc.ns.uri(prefix()));
  }

  /**
   * Constructor for converting a Java QName.
   * @param qn qname
   */
  public QNm(final QName qn) {
    this(token(qn.getPrefix().isEmpty() ? qn.getLocalPart() :
      qn.getPrefix() + ':' + qn.getLocalPart()), token(qn.getNamespaceURI()));
  }

  /**
   * Sets the URI of this QName.
   * @param u the uri to be set
   */
  public void uri(final byte[] u) {
    uri = u == null ? null : norm(u);
  }

  /**
   * Returns the URI of this QName.
   * @return uri
   */
  public byte[] uri() {
    return uri == null ? EMPTY : uri;
  }

  /**
   * Checks if the URI of this QName has been explicitly set.
   * @return result of check
   */
  public boolean hasURI() {
    return uri != null;
  }

  @Override
  public byte[] string(final InputInfo ii) {
    return name;
  }

  /**
   * Returns the string value.
   * @return string value
   */
  public byte[] string() {
    return name;
  }

  @Override
  public boolean bool(final InputInfo ii) throws QueryException {
    throw CONDTYPE.thrw(ii, type, this);
  }

  @Override
  public boolean eq(final InputInfo ii, final Item it) {
    // at this stage, item will always be of the same type
    return eq((QNm) it);
  }

  /**
   * Compares the specified item.
   * @param n name to be compared
   * @return result of check
   */
  public boolean eq(final QNm n) {
    return n == this || Token.eq(local(), n.local()) &&
        Token.eq(uri(), n.uri());
  }

  @Override
  public int diff(final InputInfo ii, final Item it) throws QueryException {
    throw Err.diff(ii, it, this);
  }

  /**
   * Checks if the name contains a prefix.
   * @return result of check
   */
  public boolean hasPrefix() {
    return pref != -1;
  }

  /**
   * Returns the prefix.
   * @return prefix
   */
  public byte[] prefix() {
    return pref == -1 ? EMPTY : substring(name, 0, pref);
  }

  /**
   * Returns the local name.
   * @return local name
   */
  public byte[] local() {
    return pref == -1 ? name : substring(name, pref + 1);
  }

  /**
   * Updates the values of this QName. This method is only called
   * to speed up internal operations.
   * @param n name
   * @param u URI
   */
  void update(final byte[] n, final byte[] u) {
    name = n;
    pref = indexOf(name, ':');
    uri = u;
  }

  @Override
  public QName toJava() {
    return new QName(Token.string(uri()), Token.string(local()),
        Token.string(prefix()));
  }

  /**
   * Returns the EQName notation.
   * @return full name
   */
  public byte[] eqname() {
    return new TokenBuilder().add('"').add(Str.get(uri()).toString()).
        add("\":").add(local()).finish();
  }

  @Override
  public int hash(final InputInfo ii) throws QueryException {
    return Token.hash(local());
  }

  @Override
  public String toString() {
    return Util.info("\"%\"", name);
  }
}