[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16509539#comment-16509539
]
ASF GitHub Bot commented on JENA-1559:
--
Github user asfgit closed the pull request at:
https://github.com/apache/jena/pull/431
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16509535#comment-16509535
]
ASF subversion and git services commented on JENA-1559:
---
Commit 2377f47e72e499e545f6d1154e287bc2cc0b5acc in jena's branch
refs/heads/master from [~an...@apache.org]
[ https://git-wip-us.apache.org/repos/asf?p=jena.git;h=2377f47 ]
JENA-1559: PrefixMappingBase - algorithm and storage separation
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16509537#comment-16509537
]
ASF subversion and git services commented on JENA-1559:
---
Commit 481e5894f29c75d7fdf9edadc027374b58f863ee in jena's branch
refs/heads/master from [~an...@apache.org]
[ https://git-wip-us.apache.org/repos/asf?p=jena.git;h=481e589 ]
JENA-1559: Merge commit 'refs/pull/431/head' of https://github.com/apache/jena
This closes #431.
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16508058#comment-16508058
]
ASF GitHub Bot commented on JENA-1559:
--
Github user afs commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194405024
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingBase.java ---
@@ -0,0 +1,277 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.StringJoiner;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.ext.xerces.util.XMLChar;
+import org.apache.jena.shared.PrefixMapping;
+import org.apache.jena.util.SplitIRI;
+
+/**
+ * Framework for implementing {@link PrefixMapping}. It is stateless
(unlike
+ * {@code PrefixMappingImpl}) and implements the contract of {@link
PrefixMapping},
+ * providing the key algorithm and delegating storage to the subclasses.
+ *
+ * Reverse mapping, looking up a URI to find a prefix is complex. There
may be several
+ * possibilities. Applications should not reliy on every implementat being
consistent,
+ * espeically when writing data when there has to be a choice on on prefix
to use to
+ * shorten a URI.
+ *
+ */
+public abstract class PrefixMappingBase implements PrefixMapping {
+/* Reverse mappings.
+ * The strict contract of PrefixMapping requires a separate
reversemapping to be storoed and manipuated
+ * which in turn adds complexity to the storage implementations.
+ * However, applications removing prefixes is unusual so we end up
with a lot of complexity with little value.
+ *
+ * Beware of the details of removing a mapping when there is another
to the same URI.
+ * If we had:
+ *
+ * Add (pref1, U)
+ * Add (pref2, U)
+ *
+ * so that {@code U} reverse maps ({@link #getNsURIPrefix}) to {@code
pref2} (it was
+ * done second) then
+ *
+ * Remove (pref2)
+ *
+ * it causes {@code U} to reverse map to {@code pref1}.
+ *
+ * This feature is quite a burden on implementations and should be
regarded as "legacy" -
+ * an implementation may not support this complex effect.
+ *
+ * PrefixMappingMem does.
+ * Database backed ones typically don't.
+ */
+
+protected PrefixMappingBase() {}
+
+// The storage operations of an implementation.
+
+/** Add prefix */
+abstract protected void add(String prefix, String uri);
+
+/** Remove prefix. */
+abstract protected void remove(String prefix);
+
+/** Clear all mappings */
+abstract protected void clear();
+
+abstract protected boolean isEmpty();
+
+abstract protected int size();
+
+/** Return the URI that the prefix maps to. */
+abstract protected String prefixToUri(String prefix);
+
+/** Return a prefix that maps to the URI.
+ * There may be several; the answer is any one of them.
+ */
+abstract protected String uriToPrefix(String uri);
+
+/** Return as a map. This map is only used within this class.
+ * It can be as efficient as possible.
+ * It will not be modifed.
+ * It wil not be retuned to a caller of {@code PrefixMappingBase}.
+ */
+abstract protected Map asMap();
+
+/**
+ * Return as a map. The map return is not connected to the prefix
mapping implementation,
+ * does not reflect subsequent prefix mapping changes.
+ */
+abstract protected Map asMapCopy();
+
+/** Apply the {@link BiConsumer} to each (prefix, uri) pair. */
+abstract protected void apply(BiConsumer
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16508025#comment-16508025
]
ASF GitHub Bot commented on JENA-1559:
--
Github user ajs6f commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194399107
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingOver.java ---
@@ -0,0 +1,97 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.iri.IRI;
+import org.apache.jena.riot.system.PrefixMap;
+
+public class PrefixMappingOver extends PrefixMappingBase {
--- End diff --
Can't speak for @rvesse, but "Adaptor" is even better to my eye.
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16508013#comment-16508013
]
ASF GitHub Bot commented on JENA-1559:
--
Github user afs commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194398068
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingOver.java ---
@@ -0,0 +1,97 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.iri.IRI;
+import org.apache.jena.riot.system.PrefixMap;
+
+public class PrefixMappingOver extends PrefixMappingBase {
--- End diff --
Its real name is `PrefixMappingOverPrefixMap` ... seemed a bit long and
confusing.
It does not seem to be a decorator. Would "Adapter" be OK?
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16507906#comment-16507906
]
ASF GitHub Bot commented on JENA-1559:
--
Github user ajs6f commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194364163
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingOver.java ---
@@ -0,0 +1,97 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.iri.IRI;
+import org.apache.jena.riot.system.PrefixMap;
+
+public class PrefixMappingOver extends PrefixMappingBase {
--- End diff --
+1
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16507839#comment-16507839
]
ASF GitHub Bot commented on JENA-1559:
--
Github user rvesse commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194339397
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingOver.java ---
@@ -0,0 +1,97 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.iri.IRI;
+import org.apache.jena.riot.system.PrefixMap;
+
+public class PrefixMappingOver extends PrefixMappingBase {
--- End diff --
Would `PrefixMappingDecorator` be a more descriptive name?
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16507837#comment-16507837
]
ASF GitHub Bot commented on JENA-1559:
--
Github user rvesse commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194338419
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingBase.java ---
@@ -0,0 +1,277 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.StringJoiner;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.ext.xerces.util.XMLChar;
+import org.apache.jena.shared.PrefixMapping;
+import org.apache.jena.util.SplitIRI;
+
+/**
+ * Framework for implementing {@link PrefixMapping}. It is stateless
(unlike
+ * {@code PrefixMappingImpl}) and implements the contract of {@link
PrefixMapping},
+ * providing the key algorithm and delegating storage to the subclasses.
+ *
+ * Reverse mapping, looking up a URI to find a prefix is complex. There
may be several
+ * possibilities. Applications should not reliy on every implementat being
consistent,
+ * espeically when writing data when there has to be a choice on on prefix
to use to
+ * shorten a URI.
+ *
+ */
+public abstract class PrefixMappingBase implements PrefixMapping {
+/* Reverse mappings.
+ * The strict contract of PrefixMapping requires a separate
reversemapping to be storoed and manipuated
--- End diff --
Typos:
- Missing space in `reverse mapping`
- `storoed`
- `manipuated`
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16507836#comment-16507836
]
ASF GitHub Bot commented on JENA-1559:
--
Github user rvesse commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194338271
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingBase.java ---
@@ -0,0 +1,277 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.StringJoiner;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.ext.xerces.util.XMLChar;
+import org.apache.jena.shared.PrefixMapping;
+import org.apache.jena.util.SplitIRI;
+
+/**
+ * Framework for implementing {@link PrefixMapping}. It is stateless
(unlike
+ * {@code PrefixMappingImpl}) and implements the contract of {@link
PrefixMapping},
+ * providing the key algorithm and delegating storage to the subclasses.
+ *
+ * Reverse mapping, looking up a URI to find a prefix is complex. There
may be several
+ * possibilities. Applications should not reliy on every implementat being
consistent,
--- End diff --
Typos
- `implementat` this line
- `espeically` on the following line
> Avoid unnecessary prefix loading in GraphPrefixesProjection
>
>
> Key: JENA-1559
> URL: https://issues.apache.org/jira/browse/JENA-1559
> Project: Apache Jena
> Issue Type: Task
>Affects Versions: Jena 3.7.0
>Reporter: Andy Seaborne
>Assignee: Andy Seaborne
>Priority: Major
>
> {{GraphPrefixesProjection}} loads all prefixes from the database (JENA-81).
> It was done that way because {{PrefixMappingImpl}} has internal
> datastructures that are not passing through lookup misses.
> Load as needed and rework the way the prefix implementation to cleanly
> separate algorithms from storage.
> Leave {{PrefixMappingImpl}} untouched - its name and details are too
> well-known.
>
>
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
[jira] [Commented] (JENA-1559) Avoid unnecessary prefix loading in GraphPrefixesProjection
[
https://issues.apache.org/jira/browse/JENA-1559?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel=16507838#comment-16507838
]
ASF GitHub Bot commented on JENA-1559:
--
Github user rvesse commented on a diff in the pull request:
https://github.com/apache/jena/pull/431#discussion_r194338879
--- Diff:
jena-arq/src/main/java/org/apache/jena/sparql/graph/PrefixMappingBase.java ---
@@ -0,0 +1,277 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.sparql.graph;
+
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
+import java.util.StringJoiner;
+import java.util.function.BiConsumer;
+
+import org.apache.jena.ext.xerces.util.XMLChar;
+import org.apache.jena.shared.PrefixMapping;
+import org.apache.jena.util.SplitIRI;
+
+/**
+ * Framework for implementing {@link PrefixMapping}. It is stateless
(unlike
+ * {@code PrefixMappingImpl}) and implements the contract of {@link
PrefixMapping},
+ * providing the key algorithm and delegating storage to the subclasses.
+ *
+ * Reverse mapping, looking up a URI to find a prefix is complex. There
may be several
+ * possibilities. Applications should not reliy on every implementat being
consistent,
+ * espeically when writing data when there has to be a choice on on prefix
to use to
+ * shorten a URI.
+ *
+ */
+public abstract class PrefixMappingBase implements PrefixMapping {
+/* Reverse mappings.
+ * The strict contract of PrefixMapping requires a separate
reversemapping to be storoed and manipuated
+ * which in turn adds complexity to the storage implementations.
+ * However, applications removing prefixes is unusual so we end up
with a lot of complexity with little value.
+ *
+ * Beware of the details of removing a mapping when there is another
to the same URI.
+ * If we had:
+ *
+ * Add (pref1, U)
+ * Add (pref2, U)
+ *
+ * so that {@code U} reverse maps ({@link #getNsURIPrefix}) to {@code
pref2} (it was
+ * done second) then
+ *
+ * Remove (pref2)
+ *
+ * it causes {@code U} to reverse map to {@code pref1}.
+ *
+ * This feature is quite a burden on implementations and should be
regarded as "legacy" -
+ * an implementation may not support this complex effect.
+ *
+ * PrefixMappingMem does.
+ * Database backed ones typically don't.
+ */
+
+protected PrefixMappingBase() {}
+
+// The storage operations of an implementation.
+
+/** Add prefix */
+abstract protected void add(String prefix, String uri);
+
+/** Remove prefix. */
+abstract protected void remove(String prefix);
+
+/** Clear all mappings */
+abstract protected void clear();
+
+abstract protected boolean isEmpty();
+
+abstract protected int size();
+
+/** Return the URI that the prefix maps to. */
+abstract protected String prefixToUri(String prefix);
+
+/** Return a prefix that maps to the URI.
+ * There may be several; the answer is any one of them.
+ */
+abstract protected String uriToPrefix(String uri);
+
+/** Return as a map. This map is only used within this class.
+ * It can be as efficient as possible.
+ * It will not be modifed.
+ * It wil not be retuned to a caller of {@code PrefixMappingBase}.
+ */
+abstract protected Map asMap();
+
+/**
+ * Return as a map. The map return is not connected to the prefix
mapping implementation,
+ * does not reflect subsequent prefix mapping changes.
+ */
+abstract protected Map asMapCopy();
+
+/** Apply the {@link BiConsumer} to each (prefix, uri) pair. */
+abstract protected void
