sqlexecutor.java

本套系统采用了业界当前最为流行的beanAction组件

      hasMoreResults = moveToNextResultsIfPresent(stmt);
    }
    return rs;
  }

  private boolean moveToNextResultsIfPresent(Statement stmt) throws SQLException {
    boolean moreResults;
    // This is the messed up JDBC approach for determining if there are more results
    moreResults = !(((moveToNextResultsSafely(stmt) == false) && (stmt.getUpdateCount() == -1)));
    return moreResults;
  }

  private boolean moveToNextResultsSafely(Statement stmt) throws SQLException {
    if (!stmt.getConnection().getMetaData().supportsMultipleResultSets()) {
      return false;
    }
    return stmt.getMoreResults();
  }

  private void handleResults(RequestScope request, ResultSet rs, int skipResults, int maxResults, RowHandlerCallback callback) throws SQLException {
    try {
      request.setResultSet(rs);
      ResultMap resultMap = request.getResultMap();
      if (resultMap != null) {
        // Skip Results
        if (rs.getType() != ResultSet.TYPE_FORWARD_ONLY) {
          if (skipResults > 0) {
            rs.absolute(skipResults);
          }
        } else {
          for (int i = 0; i < skipResults; i++) {
            if (!rs.next()) {
              return;
            }
          }
        }

        // Get Results
        int resultsFetched = 0;
        while ((maxResults == SqlExecutor.NO_MAXIMUM_RESULTS || resultsFetched < maxResults) && rs.next()) {
          Object[] columnValues = resultMap.resolveSubMap(request, rs).getResults(request, rs);
          callback.handleResultObject(request, columnValues, rs);
          resultsFetched++;
        }
      }
    } finally {
      request.setResultSet(null);
    }
  }

  private void retrieveOutputParameters(RequestScope request, CallableStatement cs, ParameterMapping[] mappings, Object[] parameters, RowHandlerCallback callback) throws SQLException {
    for (int i = 0; i < mappings.length; i++) {
      BasicParameterMapping mapping = ((BasicParameterMapping) mappings[i]);
      if (mapping.isOutputAllowed()) {
        if ("java.sql.ResultSet".equalsIgnoreCase(mapping.getJavaTypeName())) {
          ResultSet rs = (ResultSet) cs.getObject(i + 1);
          ResultMap resultMap;
          if (mapping.getResultMapName() == null) {
            resultMap = request.getResultMap();
            handleOutputParameterResults(request, resultMap, rs, callback);
          } else {
            ExtendedSqlMapClient client = (ExtendedSqlMapClient) request.getSession().getSqlMapClient();
            resultMap = client.getDelegate().getResultMap(mapping.getResultMapName());
            DefaultRowHandler rowHandler = new DefaultRowHandler();
            RowHandlerCallback handlerCallback = new RowHandlerCallback(resultMap, null, rowHandler);
            handleOutputParameterResults(request, resultMap, rs, handlerCallback);
            parameters[i] = rowHandler.getList();
          }
          rs.close();
        } else {
          parameters[i] = mapping.getTypeHandler().getResult(cs, i + 1);
        }
      }
    }
  }

  private void registerOutputParameters(CallableStatement cs, ParameterMapping[] mappings) throws SQLException {
    for (int i = 0; i < mappings.length; i++) {
      BasicParameterMapping mapping = ((BasicParameterMapping) mappings[i]);
      if (mapping.isOutputAllowed()) {
        if (null != mapping.getTypeName() && !mapping.getTypeName().equals("")) { //@added
          cs.registerOutParameter(i + 1, mapping.getJdbcType(), mapping.getTypeName());
        } else {
          if (mapping.getNumericScale() != null && (mapping.getJdbcType() == Types.NUMERIC || mapping.getJdbcType() == Types.DECIMAL))
          {
            cs.registerOutParameter(i + 1, mapping.getJdbcType(), mapping.getNumericScale().intValue());
          } else {
            cs.registerOutParameter(i + 1, mapping.getJdbcType());
          }
        }
      }
    }
  }

  private void handleOutputParameterResults(RequestScope request, ResultMap resultMap, ResultSet rs, RowHandlerCallback callback) throws SQLException {
    ResultMap orig = request.getResultMap();
    try {
      request.setResultSet(rs);
      if (resultMap != null) {
        request.setResultMap(resultMap);

        // Get Results
        while (rs.next()) {
          Object[] columnValues = resultMap.resolveSubMap(request, rs).getResults(request, rs);
          callback.handleResultObject(request, columnValues, rs);
        }
      }
    } finally {
      request.setResultSet(null);
      request.setResultMap(orig);
    }
  }

  /**
   * Clean up any batches on the session
   *
   * @param session - the session to clean up
   */
  public void cleanup(SessionScope session) {
    Batch batch = (Batch) session.getBatch();
    if (batch != null) {
      batch.cleanupBatch(session);
      session.setBatch(null);
    }
  }

  private PreparedStatement prepareStatement(SessionScope session, Connection conn, String sql, Integer rsType) throws SQLException {
    SqlMapExecutorDelegate delegate = ((ExtendedSqlMapClient)session.getSqlMapExecutor()).getDelegate();
    if (session.hasPreparedStatementFor(sql)) {
      return session.getPreparedStatement((sql));
    } else {
      PreparedStatement ps = conn.prepareStatement(sql, rsType.intValue(), ResultSet.CONCUR_READ_ONLY);
      session.putPreparedStatement(delegate, sql, ps);
      return ps;
    }
  }

  private CallableStatement prepareCall(SessionScope session, Connection conn, String sql, Integer rsType) throws SQLException {
    SqlMapExecutorDelegate delegate = ((ExtendedSqlMapClient)session.getSqlMapExecutor()).getDelegate();
    if (session.hasPreparedStatementFor(sql)) {
      return (CallableStatement) session.getPreparedStatement((sql));
    } else {
      CallableStatement cs = conn.prepareCall(sql, rsType.intValue(), ResultSet.CONCUR_READ_ONLY);
      session.putPreparedStatement(delegate, sql, cs);
      return cs;
    }
  }

  private static PreparedStatement prepareStatement(SessionScope session, Connection conn, String sql) throws SQLException {
    SqlMapExecutorDelegate delegate = ((ExtendedSqlMapClient)session.getSqlMapExecutor()).getDelegate();
    if (session.hasPreparedStatementFor(sql)) {
      return session.getPreparedStatement((sql));
    } else {
      PreparedStatement ps = conn.prepareStatement(sql);
      session.putPreparedStatement(delegate, sql, ps);
      return ps;
    }
  }

  private CallableStatement prepareCall(SessionScope session, Connection conn, String sql) throws SQLException {
    SqlMapExecutorDelegate delegate = ((ExtendedSqlMapClient)session.getSqlMapExecutor()).getDelegate();
    if (session.hasPreparedStatementFor(sql)) {
      return (CallableStatement) session.getPreparedStatement((sql));
    } else {
      CallableStatement cs = conn.prepareCall(sql);
      session.putPreparedStatement(delegate, sql, cs);
      return cs;
    }
  }

  private static void closeStatement(SessionScope session, PreparedStatement ps) {
    if (ps != null) {
      if (!session.hasPreparedStatement(ps)) {
        try {
          ps.close();
        } catch (SQLException e) {
          // ignore
        }
      }
    }
  }

  /**
   * @param rs
   */
  private static void closeResultSet(ResultSet rs) {
    if (rs != null) {
      try {
        rs.close();
      } catch (SQLException e) {
        // ignore
      }
    }
  }

  private static void setStatementTimeout(MappedStatement mappedStatement, Statement statement) throws SQLException {
    if (mappedStatement.getTimeout() != null) {
      statement.setQueryTimeout(mappedStatement.getTimeout().intValue());
    }
  }

  //
  // Inner Classes
  //

  private static class Batch {
    private String currentSql;
    private List statementList = new ArrayList();
    private List batchResultList = new ArrayList();
    private int size;

    /**
     * Create a new batch
     */
    public Batch() {
      this.size = 0;
    }

    /**
     * Getter for the batch size
     *
     * @return - the batch size
     */
    public int getSize() {
      return size;
    }

    /**
     * Add a prepared statement to the batch
     *
     * @param request    - the request scope
     * @param conn       - the database connection
     * @param sql        - the SQL to add
     * @param parameters - the parameters for the SQL
     * @throws SQLException - if the prepare for the SQL fails
     */
    public void addBatch(RequestScope request, Connection conn, String sql, Object[] parameters) throws SQLException {
      PreparedStatement ps = null;
      if (currentSql != null && sql.hashCode() == currentSql.hashCode() && sql.length() == currentSql.length()) {
        int last = statementList.size() - 1;
        ps = (PreparedStatement) statementList.get(last);
      } else {
        ps = prepareStatement(request.getSession(), conn, sql);
        setStatementTimeout(request.getStatement(), ps);
        currentSql = sql;
        statementList.add(ps);
        batchResultList.add(new BatchResult(request.getStatement().getId(), sql));
      }
      request.getParameterMap().setParameters(request, ps, parameters);
      ps.addBatch();
      size++;
    }

    /**
     * TODO (Jeff Butler) - maybe this method should be deprecated in some release,
     * and then removed in some even later release.  executeBatchDetailed gives
     * much more complete information.
     * <p/>
     * Execute the current session's batch
     *
     * @return - the number of rows updated
     * @throws SQLException - if the batch fails
     */
    public int executeBatch() throws SQLException {
      int totalRowCount = 0;
      for (int i = 0, n = statementList.size(); i < n; i++) {
        PreparedStatement ps = (PreparedStatement) statementList.get(i);
        int[] rowCounts = ps.executeBatch();
        for (int j = 0; j < rowCounts.length; j++) {
          if (rowCounts[j] == Statement.SUCCESS_NO_INFO) {
            // do nothing
          } else if (rowCounts[j] == Statement.EXECUTE_FAILED) {
            throw new SQLException("The batched statement at index " + j + " failed to execute.");
          } else {
            totalRowCount += rowCounts[j];
          }
        }
      }
      return totalRowCount;
    }

    /**
     * Batch execution method that returns all the information
     * the driver has to offer.
     *
     * @return a List of BatchResult objects
     * @throws BatchException (an SQLException sub class) if any nested
     *                        batch fails
     * @throws SQLException   if a database access error occurs, or the drive
     *                        does not support batch statements
     * @throws BatchException if the driver throws BatchUpdateException
     */
    public List executeBatchDetailed() throws SQLException, BatchException {
      List answer = new ArrayList();
      for (int i = 0, n = statementList.size(); i < n; i++) {
        BatchResult br = (BatchResult) batchResultList.get(i);
        PreparedStatement ps = (PreparedStatement) statementList.get(i);
        try {
          br.setUpdateCounts(ps.executeBatch());
        } catch (BatchUpdateException e) {
          StringBuffer message = new StringBuffer();
          message.append("Sub batch number ");
          message.append(i + 1);
          message.append(" failed.");
          if (i > 0) {
            message.append(" ");
            message.append(i);
            message.append(" prior sub batch(s) completed successfully, but will be rolled back.");
          }
          throw new BatchException(message.toString(), e, answer, br.getStatementId(), br.getSql());
        }
        answer.add(br);
      }
      return answer;
    }

    /**
     * Close all the statements in the batch and clear all the statements
     *
     * @param session
     */
    public void cleanupBatch(SessionScope session) {
      for (int i = 0, n = statementList.size(); i < n; i++) {
        PreparedStatement ps = (PreparedStatement) statementList.get(i);
        closeStatement(session, ps);
      }
      currentSql = null;
      statementList.clear();
      batchResultList.clear();
      size = 0;
    }
  }

  private void setupResultObjectFactory(RequestScope request) {
    ExtendedSqlMapClient client = (ExtendedSqlMapClient) request.getSession().getSqlMapClient();
    ResultObjectFactoryUtil.setResultObjectFactory(client.getResultObjectFactory());
    ResultObjectFactoryUtil.setStatementId(request.getStatement().getId());
  }
}