DatabaseXmlUtils.java

package org.springframework.roo.addon.dbre.addon.model;

import java.io.InputStream;
import java.util.EmptyStackException;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Set;

import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.apache.commons.lang3.StringUtils;
import org.springframework.roo.model.JavaPackage;
import org.springframework.roo.support.util.XmlUtils;
import org.w3c.dom.Comment;
import org.w3c.dom.Document;
import org.w3c.dom.Element;

/**
 * Assists converting a {@link Database} to and from XML using DOM or SAX.
 * 
 * @author Alan Stewart
 * @author Juan Carlos García
 * @since 1.1
 */
public abstract class DatabaseXmlUtils {

  public static enum IndexType {
    INDEX, UNIQUE
  }

  public static final String DESCRIPTION = "description";
  public static final String FOREIGN = "foreign";
  public static final String FOREIGN_TABLE = "foreignTable";
  public static final String LOCAL = "local";
  public static final String NAME = "name";
  public static final String ON_DELETE = "onDelete";
  public static final String ON_UPDATE = "onUpdate";
  public static final String REFERENCE = "reference";

  /**
   * Adds an <option key="foo" value="true"> element as a child of the given
   * parent element
   * 
   * @param document the XML document containing the parent and child
   *            (required)
   * @param parent the parent element to which to add a child (required)
   * @param key the option key/name (required)
   * @param value the option value
   */
  private static void addBooleanOptionElement(final Document document, final Element parent,
      final String key, final boolean value) {
    parent.appendChild(createOptionElement(key, String.valueOf(value), document));
  }

  private static void addForeignKeyElements(final Set<ForeignKey> foreignKeys,
      final boolean exported, final Element tableElement, final Document document) {
    for (final ForeignKey foreignKey : foreignKeys) {
      final Element foreignKeyElement = document.createElement("foreign-key");
      foreignKeyElement.setAttribute(NAME, foreignKey.getName());
      foreignKeyElement.setAttribute(FOREIGN_TABLE, foreignKey.getForeignTableName());
      foreignKeyElement.setAttribute(ON_DELETE, foreignKey.getOnDelete().getCode());
      foreignKeyElement.setAttribute(ON_UPDATE, foreignKey.getOnUpdate().getCode());

      final String foreignSchemaName = foreignKey.getForeignSchemaName();
      if (!DbreModelService.NO_SCHEMA_REQUIRED.equals(foreignSchemaName)) {
        foreignKeyElement.appendChild(createOptionElement("foreignSchemaName", foreignSchemaName,
            document));
      }

      foreignKeyElement.appendChild(createOptionElement("exported", String.valueOf(exported),
          document));

      for (final Reference reference : foreignKey.getReferences()) {
        final Element referenceElement = document.createElement(REFERENCE);
        referenceElement.setAttribute(FOREIGN, reference.getForeignColumnName());
        referenceElement.setAttribute(LOCAL, reference.getLocalColumnName());
        foreignKeyElement.appendChild(referenceElement);
      }
      tableElement.appendChild(foreignKeyElement);
    }
  }

  private static void addIndices(final Table table, final Element tableElement,
      final IndexType indexType) {
    final List<Element> elements =
        XmlUtils.findElements(indexType.name().toLowerCase(), tableElement);
    for (final Element element : elements) {
      final Index index = new Index(element.getAttribute(NAME));
      index.setUnique(indexType == IndexType.UNIQUE);
      final List<Element> indexColumnElements =
          XmlUtils.findElements(indexType.name().toLowerCase() + "-column", element);
      for (final Element indexColumnElement : indexColumnElements) {
        final IndexColumn indexColumn = new IndexColumn(indexColumnElement.getAttribute(NAME));
        index.addColumn(indexColumn);
      }
      table.addIndex(index);
    }
  }

  private static Element createOptionElement(final String key, final String value,
      final Document document) {
    final Element option = document.createElement("option");
    option.setAttribute("key", key);
    option.setAttribute("value", value);
    return option;
  }

  public static Document getDatabaseDocument(final Database database) {
    final Document document = XmlUtils.getDocumentBuilder().newDocument();
    final Comment comment =
        document
            .createComment("WARNING: DO NOT EDIT THIS FILE. THIS FILE IS MANAGED BY SPRING ROO.");
    document.appendChild(comment);

    final Element databaseElement = document.createElement("database");
    databaseElement.setAttribute(NAME, "deprecated");

    if (database.getDestinationPackage() != null) {
      databaseElement.setAttribute("package", database.getDestinationPackage()
          .getFullyQualifiedPackageName());
    }

    databaseElement.appendChild(createOptionElement("moduleName", database.getModuleName(),
        document));
    addBooleanOptionElement(document, databaseElement, "repository", database.isRepository());
    addBooleanOptionElement(document, databaseElement, "service", database.isService());
    addBooleanOptionElement(document, databaseElement, "includeNonPortableAttributes",
        database.isIncludeNonPortableAttributes());
    addBooleanOptionElement(document, databaseElement, "disableVersionFields",
        database.isDisableVersionFields());
    addBooleanOptionElement(document, databaseElement, "disableGeneratedIdentifiers",
        database.isDisableGeneratedIdentifiers());
    addBooleanOptionElement(document, databaseElement, "testAutomatically",
        database.isTestAutomatically());

    for (final Table table : database.getTables()) {
      final Element tableElement = document.createElement("table");
      tableElement.setAttribute(NAME, table.getName());
      final String schemaName = table.getSchema().getName();
      if (!DbreModelService.NO_SCHEMA_REQUIRED.equals(schemaName)) {
        tableElement.setAttribute("alias", schemaName);
      }
      if (StringUtils.isNotBlank(table.getDescription())) {
        tableElement.setAttribute(DESCRIPTION, table.getDescription());
      }

      for (final Column column : table.getColumns()) {
        final Element columnElement = document.createElement("column");
        columnElement.setAttribute(NAME, column.getName());
        if (StringUtils.isNotBlank(column.getDescription())) {
          columnElement.setAttribute(DESCRIPTION, column.getDescription());
        }

        columnElement.setAttribute("primaryKey", String.valueOf(column.isPrimaryKey()));
        columnElement.setAttribute("required", String.valueOf(column.isRequired()));
        columnElement.setAttribute("size", String.valueOf(column.getColumnSize()));
        columnElement.setAttribute("scale", String.valueOf(column.getScale()));
        columnElement.setAttribute("type", column.getDataType() + "," + column.getTypeName());

        tableElement.appendChild(columnElement);
      }

      addForeignKeyElements(table.getImportedKeys(), false, tableElement, document);
      addForeignKeyElements(table.getExportedKeys(), true, tableElement, document);

      for (final Index index : table.getIndices()) {
        final Element indexElement =
            document.createElement(index.isUnique() ? IndexType.UNIQUE.name().toLowerCase()
                : IndexType.INDEX.name().toLowerCase());
        indexElement.setAttribute(NAME, index.getName());
        for (final IndexColumn indexColumn : index.getColumns()) {
          final Element indexColumnElement =
              document.createElement((index.isUnique() ? IndexType.UNIQUE.name().toLowerCase()
                  : IndexType.INDEX.name().toLowerCase()) + "-column");
          indexColumnElement.setAttribute(NAME, indexColumn.getName());
          indexElement.appendChild(indexColumnElement);
        }
        tableElement.appendChild(indexElement);
      }

      databaseElement.appendChild(tableElement);
    }

    document.appendChild(databaseElement);

    // ROO-2355: transformer.setOutputProperty(OutputKeys.DOCTYPE_SYSTEM,
    // "http://db.apache.org/torque/dtd/database_3_3.dtd");

    return document;
  }

  static Database readDatabase(final InputStream inputStream) {
    try {
      final SAXParserFactory spf = SAXParserFactory.newInstance();
      final SAXParser parser = spf.newSAXParser();
      final DatabaseContentHandler contentHandler = new DatabaseContentHandler();
      parser.parse(inputStream, contentHandler);
      return contentHandler.getDatabase();
    } catch (final EmptyStackException e) {
      throw new IllegalStateException("Unable to read database from XML file", e);
    } catch (final Exception e) {
      if (e.getMessage().contains("Invalid byte")) {
        throw new IllegalStateException(
            "Invalid content in XML file. There may hidden characters in the file, such as the byte order mark (BOM). Try re-saving the xml in a text editor",
            e);
      }
      throw new IllegalStateException(e);
    }
  }

  static Database readDatabaseWithDom(final InputStream inputStream) {
    final Document document = XmlUtils.readXml(inputStream);
    final Element databaseElement = document.getDocumentElement();

    final Set<Table> tables = new LinkedHashSet<Table>();

    final List<Element> tableElements = XmlUtils.findElements("table", databaseElement);
    for (final Element tableElement : tableElements) {
      final String alias = tableElement.getAttribute("alias");
      final String schemaName =
          StringUtils.defaultIfEmpty(alias, databaseElement.getAttribute(NAME));
      final Table table = new Table(tableElement.getAttribute(NAME), new Schema(schemaName));
      if (StringUtils.isNotBlank(tableElement.getAttribute(DESCRIPTION))) {
        table.setDescription(tableElement.getAttribute(DESCRIPTION));
      }

      final List<Element> columnElements = XmlUtils.findElements("column", tableElement);
      for (final Element columnElement : columnElements) {
        final String type = columnElement.getAttribute("type");
        final String[] dataTypeAndName = StringUtils.split(type, ",");
        final int dataType = Integer.parseInt(dataTypeAndName[0]);
        final String typeName = dataTypeAndName[1];

        final int columnSize = Integer.parseInt(columnElement.getAttribute("size"));
        final int scale = Integer.parseInt(columnElement.getAttribute("scale"));

        final Column column =
            new Column(columnElement.getAttribute(NAME), dataType, typeName, columnSize, scale);
        column.setDescription(columnElement.getAttribute(DESCRIPTION));
        column.setPrimaryKey(Boolean.parseBoolean(columnElement.getAttribute("primaryKey")));
        column.setRequired(Boolean.parseBoolean(columnElement.getAttribute("required")));

        table.addColumn(column);
      }

      final List<Element> foreignKeyElements = XmlUtils.findElements("foreign-key", tableElement);
      for (final Element foreignKeyElement : foreignKeyElements) {
        final ForeignKey foreignKey =
            new ForeignKey(foreignKeyElement.getAttribute(NAME),
                foreignKeyElement.getAttribute(FOREIGN_TABLE));
        foreignKey.setOnDelete(CascadeAction.getCascadeAction(foreignKeyElement
            .getAttribute(ON_DELETE)));
        foreignKey.setOnUpdate(CascadeAction.getCascadeAction(foreignKeyElement
            .getAttribute(ON_UPDATE)));

        final List<Element> optionElements = XmlUtils.findElements("option", foreignKeyElement);
        for (final Element optionElement : optionElements) {
          final String key = optionElement.getAttribute("key");
          final String value = optionElement.getAttribute("value");
          if (key.equals("exported")) {
            foreignKey.setExported(Boolean.parseBoolean(value));
          }
          if (key.equals("foreignSchemaName")) {
            foreignKey.setForeignSchemaName(value);
          }
        }

        final List<Element> referenceElements = XmlUtils.findElements(REFERENCE, foreignKeyElement);
        for (final Element referenceElement : referenceElements) {
          final Reference reference =
              new Reference(referenceElement.getAttribute(LOCAL),
                  referenceElement.getAttribute(FOREIGN));
          foreignKey.addReference(reference);
        }
        table.addImportedKey(foreignKey);
      }

      addIndices(table, tableElement, IndexType.INDEX);
      addIndices(table, tableElement, IndexType.UNIQUE);

      tables.add(table);
    }

    JavaPackage destinationPackage = null;
    if (StringUtils.isNotBlank(databaseElement.getAttribute("package"))) {
      destinationPackage = new JavaPackage(databaseElement.getAttribute("package"));
    }

    final Database database = new Database(tables);
    database.setDestinationPackage(destinationPackage);

    final List<Element> optionElements = XmlUtils.findElements("option", databaseElement);
    for (final Element optionElement : optionElements) {
      final String key = optionElement.getAttribute("key");
      final String value = optionElement.getAttribute("value");
      if (key.equals("moduleName")) {
        database.setModuleName(value);
      }
      if (key.equals("repository")) {
        database.setRepository(Boolean.parseBoolean(value));
      }
      if (key.equals("service")) {
        database.setService(Boolean.parseBoolean(value));
      }
      if (key.equals("testAutomatically")) {
        database.setTestAutomatically(Boolean.parseBoolean(value));
      }
      if (key.equals("includeNonPortableAttributes")) {
        database.setIncludeNonPortableAttributes(Boolean.parseBoolean(value));
      }
      if (key.equals("disableVersionFields")) {
        database.setDisableVersionFields(Boolean.parseBoolean(value));
      }
      if (key.equals("disableGeneratedIdentifiers")) {
        database.setDisableGeneratedIdentifiers(Boolean.parseBoolean(value));
      }
    }

    return database;
  }
}