DatabasesCollector.java

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 *
 * Pentaho Data Integration
 *
 * Copyright (C) 2002-2015 by Pentaho : http://www.pentaho.com
 *
 *******************************************************************************
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
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 * See the License for the specific language governing permissions and
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package org.pentaho.di.ui.spoon;

import org.pentaho.di.base.AbstractMeta;
import org.pentaho.di.core.database.DatabaseMeta;
import org.pentaho.di.core.exception.KettleException;
import org.pentaho.di.repository.Repository;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @author Andrey Khayrutdinov
 */
public class DatabasesCollector {
  private final AbstractMeta meta;
  private final Repository repository;

  private List<String> dbNames;
  private Map<String, DatabaseMeta> names2metas;

  public DatabasesCollector( AbstractMeta meta, Repository repository ) {
    this.meta = meta;
    this.repository = repository;
  }

  public void collectDatabases() throws KettleException {
    List<DatabaseMeta> dbsFromMeta = meta.getDatabases();
    names2metas = new HashMap<String, DatabaseMeta>( dbsFromMeta.size() );
    for ( DatabaseMeta db : dbsFromMeta ) {
      names2metas.put( db.getName(), db );
    }

    if ( repository != null ) {
      List<DatabaseMeta> dbsFromRepo = repository.readDatabases();
      for ( DatabaseMeta db : dbsFromRepo ) {
        if ( !names2metas.containsKey( db.getName() ) ) {
          names2metas.put( db.getName(), db );
        }
      }
    }

    dbNames = new ArrayList<String>( names2metas.keySet() );
    Collections.sort( dbNames, String.CASE_INSENSITIVE_ORDER );
  }

  public List<String> getDatabaseNames() {
    if ( dbNames == null ) {
      throw exception();
    }
    return Collections.unmodifiableList( dbNames );
  }

  public DatabaseMeta getMetaFor( String dbName ) {
    if ( names2metas == null ) {
      throw exception();
    }
    return names2metas.get( dbName );
  }

  private static IllegalStateException exception() {
    return new IllegalStateException( "Call collectDatabases() first" );
  }
}