Constraint.java :  » Database-ORM » hibernate » org » hibernate » mapping » Java Open Source

/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * Copyright (c) 2008, Red Hat Middleware LLC or third-party contributors as
 * indicated by the @author tags or express copyright attribution
 * statements applied by the authors.  All third-party contributions are
 * distributed under license by Red Hat Middleware LLC.
 *
 * This copyrighted material is made available to anyone wishing to use, modify,
 * copy, or redistribute it subject to the terms and conditions of the GNU
 * Lesser General Public License, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 * for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this distribution; if not, write to:
 * Free Software Foundation, Inc.
 * 51 Franklin Street, Fifth Floor
 * Boston, MA  02110-1301  USA
 *
 */
package org.hibernate.mapping;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.hibernate.dialect.Dialect;
import org.hibernate.engine.Mapping;

/**
 * A relational constraint.
 *
 * @author Gavin King
 */
public abstract class Constraint implements RelationalModel, Serializable {

  private String name;
  private final List columns = new ArrayList();
  private Table table;

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public Iterator getColumnIterator() {
    return columns.iterator();
  }

  public void addColumn(Column column) {
    if ( !columns.contains( column ) ) columns.add( column );
  }

  public void addColumns(Iterator columnIterator) {
    while ( columnIterator.hasNext() ) {
      Selectable col = (Selectable) columnIterator.next();
      if ( !col.isFormula() ) addColumn( (Column) col );
    }
  }

  /**
   * @param column
   * @return true if this constraint already contains a column with same name.
   */
  public boolean containsColumn(Column column) {
    return columns.contains( column );
  }

  public int getColumnSpan() {
    return columns.size();
  }

  public Column getColumn(int i) {
    return (Column) columns.get( i );
  }

  public Iterator columnIterator() {
    return columns.iterator();
  }

  public Table getTable() {
    return table;
  }

  public void setTable(Table table) {
    this.table = table;
  }

  public boolean isGenerated(Dialect dialect) {
    return true;
  }

  public String sqlDropString(Dialect dialect, String defaultCatalog, String defaultSchema) {
    if ( isGenerated( dialect ) ) {
      return new StringBuffer()
          .append( "alter table " )
          .append( getTable().getQualifiedName( dialect, defaultCatalog, defaultSchema ) )
          .append( " drop constraint " )
          .append( dialect.quote( getName() ) )
          .toString();
    }
    else {
      return null;
    }
  }

  public String sqlCreateString(Dialect dialect, Mapping p, String defaultCatalog, String defaultSchema) {
    if ( isGenerated( dialect ) ) {
      String constraintString = sqlConstraintString( dialect, getName(), defaultCatalog, defaultSchema );
      StringBuffer buf = new StringBuffer( "alter table " )
          .append( getTable().getQualifiedName( dialect, defaultCatalog, defaultSchema ) )
          .append( constraintString );
      return buf.toString();
    }
    else {
      return null;
    }
  }

  public List getColumns() {
    return columns;
  }

  public abstract String sqlConstraintString(Dialect d, String constraintName, String defaultCatalog,
                         String defaultSchema);

  public String toString() {
    return getClass().getName() + '(' + getTable().getName() + getColumns() + ") as " + name;
  }
}