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/*
 * Copyright DataStax, Inc.
 *
 * This software can be used solely with DataStax Enterprise. Please consult the license at
 * http://www.datastax.com/terms/datastax-dse-driver-license-terms
 */
package com.datastax.driver.core;

import com.datastax.driver.core.utils.MoreObjects;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import java.util.UUID;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * An immutable representation of a materialized view. Materialized views are available starting
 * from Cassandra 3.0.
 */
public class MaterializedViewMetadata extends AbstractTableMetadata {

  private static final Logger logger = LoggerFactory.getLogger(MaterializedViewMetadata.class);

  private volatile TableMetadata baseTable;

  private final boolean includeAllColumns;

  private final String whereClause;

  private MaterializedViewMetadata(
      KeyspaceMetadata keyspace,
      TableMetadata baseTable,
      String name,
      UUID id,
      List partitionKey,
      List clusteringColumns,
      Map columns,
      boolean includeAllColumns,
      String whereClause,
      TableOptionsMetadata options,
      List clusteringOrder,
      VersionNumber cassandraVersion) {
    super(
        keyspace,
        name,
        id,
        partitionKey,
        clusteringColumns,
        columns,
        options,
        clusteringOrder,
        cassandraVersion);
    this.baseTable = baseTable;
    this.includeAllColumns = includeAllColumns;
    this.whereClause = whereClause;
  }

  static MaterializedViewMetadata build(
      KeyspaceMetadata keyspace,
      Row row,
      Map rawCols,
      VersionNumber cassandraVersion,
      Cluster cluster) {

    String name = row.getString("view_name");
    String tableName = row.getString("base_table_name");
    TableMetadata baseTable = keyspace.tables.get(tableName);
    if (baseTable == null) {
      logger.trace(
          String.format(
              "Cannot find base table %s for materialized view %s.%s: "
                  + "Cluster.getMetadata().getKeyspace(\"%s\").getView(\"%s\") will return null",
              tableName, keyspace.getName(), name, keyspace.getName(), name));
      return null;
    }

    UUID id = row.getUUID("id");
    boolean includeAllColumns = row.getBool("include_all_columns");
    String whereClause = row.getString("where_clause");

    int partitionKeySize =
        findCollectionSize(rawCols.values(), ColumnMetadata.Raw.Kind.PARTITION_KEY);
    int clusteringSize =
        findCollectionSize(rawCols.values(), ColumnMetadata.Raw.Kind.CLUSTERING_COLUMN);

    List partitionKey =
        new ArrayList(Collections.nCopies(partitionKeySize, null));
    List clusteringColumns =
        new ArrayList(Collections.nCopies(clusteringSize, null));
    List clusteringOrder =
        new ArrayList(Collections.nCopies(clusteringSize, null));

    // We use a linked hashmap because we will keep this in the order of a 'SELECT * FROM ...'.
    LinkedHashMap columns = new LinkedHashMap();

    TableOptionsMetadata options = null;
    try {
      options = new TableOptionsMetadata(row, false, cassandraVersion);
    } catch (RuntimeException e) {
      // See ControlConnection#refreshSchema for why we'd rather not probably this further. Since
      // table options is one thing
      // that tends to change often in Cassandra, it's worth special casing this.
      logger.error(
          String.format(
              "Error parsing schema options for view %s.%s: "
                  + "Cluster.getMetadata().getKeyspace(\"%s\").getView(\"%s\").getOptions() will return null",
              keyspace.getName(), name, keyspace.getName(), name),
          e);
    }

    MaterializedViewMetadata view =
        new MaterializedViewMetadata(
            keyspace,
            baseTable,
            name,
            id,
            partitionKey,
            clusteringColumns,
            columns,
            includeAllColumns,
            whereClause,
            options,
            clusteringOrder,
            cassandraVersion);

    // We use this temporary set just so non PK columns are added in lexicographical order, which is
    // the one of a
    // 'SELECT * FROM ...'
    Set otherColumns = new TreeSet(columnMetadataComparator);
    for (ColumnMetadata.Raw rawCol : rawCols.values()) {
      DataType dataType;
      if (cassandraVersion.getMajor() >= 3) {
        dataType =
            DataTypeCqlNameParser.parse(
                rawCol.dataType,
                cluster,
                keyspace.getName(),
                keyspace.userTypes,
                keyspace.userTypes,
                false,
                false);
      } else {
        ProtocolVersion protocolVersion =
            cluster.getConfiguration().getProtocolOptions().getProtocolVersion();
        CodecRegistry codecRegistry = cluster.getConfiguration().getCodecRegistry();
        dataType =
            DataTypeClassNameParser.parseOne(rawCol.dataType, protocolVersion, codecRegistry);
      }
      ColumnMetadata col = ColumnMetadata.fromRaw(view, rawCol, dataType);
      switch (rawCol.kind) {
        case PARTITION_KEY:
          partitionKey.set(rawCol.position, col);
          break;
        case CLUSTERING_COLUMN:
          clusteringColumns.set(rawCol.position, col);
          clusteringOrder.set(
              rawCol.position, rawCol.isReversed ? ClusteringOrder.DESC : ClusteringOrder.ASC);
          break;
        default:
          otherColumns.add(col);
          break;
      }
    }
    for (ColumnMetadata c : partitionKey) columns.put(c.getName(), c);
    for (ColumnMetadata c : clusteringColumns) columns.put(c.getName(), c);
    for (ColumnMetadata c : otherColumns) columns.put(c.getName(), c);

    baseTable.add(view);

    return view;
  }

  private static int findCollectionSize(
      Collection cols, ColumnMetadata.Raw.Kind kind) {
    int maxId = -1;
    for (ColumnMetadata.Raw col : cols) if (col.kind == kind) maxId = Math.max(maxId, col.position);
    return maxId + 1;
  }

  /**
   * Return this materialized view's base table.
   *
   * @return this materialized view's base table.
   */
  public TableMetadata getBaseTable() {
    return baseTable;
  }

  /**
   * Returns a single CQL statement representing this materialized view.
   *
   * 

This method returns a single {@code CREATE MATERIALIZED VIEW} statement with the options * corresponding to the materialized view definition. * *

Note that the returned String is formatted to be human readable (for some definition of * human readable at least). * * @return the {@code CREATE MATERIALIZED VIEW} statement corresponding to this view. * @see #asCQLQuery */ @Override public String exportAsString() { return super.exportAsString(); } /** * Returns a single CQL statement representing this materialized view. * *

This method returns a single {@code CREATE MATERIALIZED VIEW} statement with the options * corresponding to the materialized view definition. * *

Note that the returned string is a single line; the returned statement is not formatted in * any way. * * @return the {@code CREATE MATERIALIZED VIEW} statement corresponding to this view. * @see #exportAsString */ @Override public String asCQLQuery() { return super.asCQLQuery(); } @Override protected String asCQLQuery(boolean formatted) { String keyspaceName = Metadata.quoteIfNecessary(keyspace.getName()); String baseTableName = Metadata.quoteIfNecessary(baseTable.getName()); String viewName = Metadata.quoteIfNecessary(name); StringBuilder sb = new StringBuilder(); sb.append("CREATE MATERIALIZED VIEW ") .append(keyspaceName) .append('.') .append(viewName) .append(" AS"); // SELECT spaceOrNewLine(sb, formatted).append("SELECT "); if (includeAllColumns) { sb.append("*"); } else { Iterator it = columns.values().iterator(); while (it.hasNext()) { ColumnMetadata column = it.next(); sb.append(Metadata.quoteIfNecessary(column.getName())); if (it.hasNext()) sb.append(", "); } } // FROM spaceOrNewLine(sb, formatted) .append("FROM ") .append(keyspaceName) .append('.') .append(baseTableName); // WHERE // the CQL grammar allows missing WHERE clauses, although C* currently disallows it if (whereClause != null && !whereClause.isEmpty()) { spaceOrNewLine(sb, formatted).append("WHERE ").append(whereClause); } // PK spaceOrNewLine(sb, formatted).append("PRIMARY KEY ("); if (partitionKey.size() == 1) { sb.append(Metadata.quoteIfNecessary(partitionKey.get(0).getName())); } else { sb.append('('); boolean first = true; for (ColumnMetadata cm : partitionKey) { if (first) first = false; else sb.append(", "); sb.append(Metadata.quoteIfNecessary(cm.getName())); } sb.append(')'); } for (ColumnMetadata cm : clusteringColumns) sb.append(", ").append(Metadata.quoteIfNecessary(cm.getName())); sb.append(')'); // append 3 extra spaces if formatted to align WITH. spaceOrNewLine(sb, formatted); appendOptions(sb, formatted); return sb.toString(); } /** * Updates the base table for this view and adds it to that table. This is used when a table * update is processed and the views need to be carried over. */ void setBaseTable(TableMetadata table) { this.baseTable = table; table.add(this); } @Override public boolean equals(Object other) { if (other == this) return true; if (!(other instanceof MaterializedViewMetadata)) return false; MaterializedViewMetadata that = (MaterializedViewMetadata) other; return MoreObjects.equal(this.name, that.name) && MoreObjects.equal(this.id, that.id) && MoreObjects.equal(this.partitionKey, that.partitionKey) && MoreObjects.equal(this.clusteringColumns, that.clusteringColumns) && MoreObjects.equal(this.columns, that.columns) && MoreObjects.equal(this.options, that.options) && MoreObjects.equal(this.clusteringOrder, that.clusteringOrder) && MoreObjects.equal(this.baseTable.getName(), that.baseTable.getName()) && this.includeAllColumns == that.includeAllColumns; } @Override public int hashCode() { return MoreObjects.hashCode( name, id, partitionKey, clusteringColumns, columns, options, clusteringOrder, baseTable.getName(), includeAllColumns); } }





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