diff options
Diffstat (limited to 'plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java')
| -rw-r--r-- | plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java | 228 |
1 files changed, 155 insertions, 73 deletions
diff --git a/plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java b/plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java index c98acee320..8dd6bc41e7 100644 --- a/plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java +++ b/plugins/org.eclipse.emf.cdo.server.db/src/org/eclipse/emf/cdo/server/internal/db/mapping/horizontal/AbstractListTableMapping.java @@ -1,5 +1,5 @@ /** - * Copyright (c) 2004 - 2009 Eike Stepper (Berlin, Germany) and others. + * Copyright (c) 2004 - 2009 Eike Stepper (Berlin, Germany) and others. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at @@ -7,7 +7,7 @@ * * Contributors: * Eike Stepper - initial API and implementation - * Stefan Winkler - major refactoring + * Stefan Winkler - 271444: [DB] Multiple refactorings https://bugs.eclipse.org/bugs/show_bug.cgi?id=271444 */ package org.eclipse.emf.cdo.server.internal.db.mapping.horizontal; @@ -44,6 +44,8 @@ import java.util.Collection; import java.util.List; /** + * This abstract base class provides basic behavior needed for mapping many-valued attributes to tables. + * * @author Eike Stepper * @author Stefan Winkler * @since 2.0 @@ -52,14 +54,27 @@ public abstract class AbstractListTableMapping implements IListMapping { private static final ContextTracer TRACER = new ContextTracer(OM.DEBUG, AbstractListTableMapping.class); + /** + * The feature for this mapping. + */ private EStructuralFeature feature; + /** + * The table of this mapping. + */ private IDBTable table; + /** + * The type mapping for the value field. + */ private ITypeMapping typeMapping; + /** + * The associated mapping strategy. + */ private IMappingStrategy mappingStrategy; + // --------- SQL strings - see initSqlStrings() ----------------- private String sqlSelectChunksPrefix; private String sqlOrderByIndex; @@ -68,6 +83,8 @@ public abstract class AbstractListTableMapping implements IListMapping private EClass containingClass; + private String sqlGetListLastIndex; + public AbstractListTableMapping(IMappingStrategy mappingStrategy, EClass eClass, EStructuralFeature feature) { this.mappingStrategy = mappingStrategy; @@ -93,11 +110,11 @@ public abstract class AbstractListTableMapping implements IListMapping } // add field for list index - IDBField idxField = table.addField(CDODBSchema.FEATURE_IDX, DBType.INTEGER); + IDBField idxField = table.addField(CDODBSchema.LIST_IDX, DBType.INTEGER); // add field for value typeMapping = mappingStrategy.createValueMapping(feature); - typeMapping.createDBField(table, CDODBSchema.FEATURE_TARGET); + typeMapping.createDBField(table, CDODBSchema.LIST_VALUE); // add table indexes table.addIndex(Type.NON_UNIQUE, dbFields); @@ -121,7 +138,7 @@ public abstract class AbstractListTableMapping implements IListMapping // ---------------- SELECT to read chunks ---------------------------- StringBuilder builder = new StringBuilder(); builder.append("SELECT "); - builder.append(CDODBSchema.FEATURE_TARGET); + builder.append(CDODBSchema.LIST_VALUE); builder.append(" FROM "); builder.append(tableName); builder.append(" WHERE "); @@ -143,7 +160,32 @@ public abstract class AbstractListTableMapping implements IListMapping sqlSelectChunksPrefix = builder.toString(); - sqlOrderByIndex = " ORDER BY " + CDODBSchema.FEATURE_IDX; + sqlOrderByIndex = " ORDER BY " + CDODBSchema.LIST_IDX; + + // ----------------- count list size -------------------------- + + builder = new StringBuilder("SELECT max("); + builder.append(CDODBSchema.LIST_IDX); + builder.append(") FROM "); + builder.append(tableName); + builder.append(" WHERE "); + + for (int i = 0; i < fields.length; i++) + { + builder.append(fields[i].getName()); + if (i + 1 < fields.length) + { + // more to come + builder.append("= ? AND "); + } + else + { + // last one + builder.append("= ? "); + } + } + + sqlGetListLastIndex = builder.toString(); // ----------------- INSERT - reference entry ----------------- builder = new StringBuilder("INSERT INTO "); @@ -177,10 +219,26 @@ public abstract class AbstractListTableMapping implements IListMapping return typeMapping; } - public void readValues(IDBStoreAccessor accessor, InternalCDORevision revision, int referenceChunk) + public void readValues(IDBStoreAccessor accessor, InternalCDORevision revision, int listChunk) { MoveableList<Object> list = revision.getList(getFeature()); + int listSize = 0; + + if (listChunk != CDORevision.UNCHUNKED) + { + listSize = getListLastIndex(accessor, revision); + if (listSize == -1) + { + // list is empty - take shortcut + return; + } + else + { + // subtract amount of items we are going to read now + listSize -= listChunk; + } + } if (TRACER.isEnabled()) { @@ -206,7 +264,7 @@ public abstract class AbstractListTableMapping implements IListMapping resultSet = pstmt.executeQuery(); - while ((referenceChunk == CDORevision.UNCHUNKED || --referenceChunk >= 0) && resultSet.next()) + while ((listChunk == CDORevision.UNCHUNKED || --listChunk >= 0) && resultSet.next()) { Object value = typeMapping.readValue(resultSet, 1); if (TRACER.isEnabled()) @@ -216,21 +274,75 @@ public abstract class AbstractListTableMapping implements IListMapping list.add(value); } - // TODO Optimize this? - while (resultSet.next()) + while (listSize-- > 0) { + list.add(InternalCDORevision.UNINITIALIZED); if (TRACER.isEnabled()) { - TRACER.format("Additional value for index {0} ignored due to chunking. Setting uninitialized.", list.size()); + TRACER.format("Added UNINITIALIZED for index {0} ", list.size()); } - - list.add(InternalCDORevision.UNINITIALIZED); } + } + catch (SQLException ex) + { + throw new DBException(ex); + } + finally + { + DBUtil.close(resultSet); + DBUtil.close(pstmt); + } + + if (TRACER.isEnabled()) + { + TRACER.format("Reading list values done for feature {0}.{1} of {2}v{3}", containingClass.getName(), feature + .getName(), revision.getID(), revision.getVersion()); + } + } + + /** + * Return the last (maximum) list index. (euals to size-1) + * + * @param accessor + * the accessor to use + * @param revision + * the revision to which the feature list belongs + * @return the last index or <code>-1</code> if the list is empty. + */ + private int getListLastIndex(IDBStoreAccessor accessor, InternalCDORevision revision) + { + PreparedStatement pstmt = null; + ResultSet resultSet = null; + + try + { + pstmt = accessor.getConnection().prepareStatement(sqlGetListLastIndex); + + setKeyFields(pstmt, revision); if (TRACER.isEnabled()) { - TRACER.format("Reading list values done for feature {0}.{1} of {2}v{3}", containingClass.getName(), feature - .getName(), revision.getID(), revision.getVersion()); + TRACER.trace(pstmt.toString()); + } + + resultSet = pstmt.executeQuery(); + + if (!resultSet.next()) + { + if (TRACER.isEnabled()) + { + TRACER.trace("No last index found -> list is empty. "); + } + return -1; + } + else + { + int result = resultSet.getInt(1); + if (TRACER.isEnabled()) + { + TRACER.trace("Read list size = " + result); + } + return result; } } catch (SQLException ex) @@ -242,7 +354,6 @@ public abstract class AbstractListTableMapping implements IListMapping DBUtil.close(resultSet); DBUtil.close(pstmt); } - } public final void readChunks(IDBStoreChunkReader chunkReader, List<Chunk> chunks, String where) @@ -338,10 +449,6 @@ public abstract class AbstractListTableMapping implements IListMapping { CDOList values = revision.getList(getFeature()); - // if(values.contains(InternalCDORevision.UNINITIALIZED)) { - // readUninitializedValues(accessor, values); - // } - int idx = 0; for (Object element : values) { @@ -349,59 +456,6 @@ public abstract class AbstractListTableMapping implements IListMapping } } - // private void readUninitializedValues(IDBStoreAccessor accessor, CDORevision revision, MoveableList<Object> values) - // { - // CDOID id = revision.getID(); - // int version = revision.getVersion(); - // - // if (TRACER.isEnabled()) - // { - // TRACER.format("Reading uninitialized list values for feature {0}.{1} of {2}v{3}", containingClass.getName(), - // feature.getName(), - // id, version); - // } - // - // PreparedStatement pstmt = null; - // ResultSet resultSet = null; - // - // try - // { - // String sql = sqlSelectChunksPrefix + sqlOrderByIndex; - // - // pstmt = accessor.getConnection().prepareStatement(sql); - // - // pstmt.setLong(1, CDOIDUtil.getLong(id)); - // pstmt.setInt(2, version); - // if (TRACER.isEnabled()) - // { - // TRACER.trace(pstmt.toString()); - // } - // - // resultSet = pstmt.executeQuery(); - // - // int index = 0; - // - // while(resultSet.next()) { - // if(values.get(index) == InternalCDORevision.UNINITIALIZED) { - // Object value = typeMapping.readValue(resultSet, 1); - // if (TRACER.isEnabled()) - // { - // TRACER.format("Read value for index {0} from result set: {1}", list.size(), value); - // } - // } - // } - // } - // catch (SQLException ex) - // { - // throw new DBException(ex); - // } - // finally - // { - // DBUtil.close(resultSet); - // DBUtil.close(pstmt); - // } - // } - protected final void writeValue(IDBStoreAccessor accessor, CDORevision revision, int idx, Object value) { PreparedStatement stmt = null; @@ -432,4 +486,32 @@ public abstract class AbstractListTableMapping implements IListMapping DBUtil.close(stmt); } } + + /** + * Used by subclasses to indicate which fields should be in the table. I.e. just a pair of name and DBType ... + * + * @author Stefan Winkler + */ + protected static class FieldInfo + { + private String name; + + private DBType dbType; + + public FieldInfo(String name, DBType dbType) + { + this.name = name; + this.dbType = dbType; + } + + public String getName() + { + return name; + } + + public DBType getDbType() + { + return dbType; + } + } } |