[OLINGO-937] Avoid call to ServiceLoader on each request

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: V2 2.0.6
• Fix Version/s: V2 2.0.7
• Component/s: odata2-core
• Labels: performance xml
• Assignee: mibo
• Reporter: Jonathan Bayle
• Created: 19/Apr/16 16:28
• Updated: 20/Apr/16 05:43
• Resolved: 20/Apr/16 05:43

Description

Dear Olingo developers,

New instances of XMLInputFactory, Transformer and XMLStreamWriter are created on each request that parses/produces XML documents.

These instances are obtained through the ServiceLoader class, which is known for being slow.

See:

These objects could be instanciated only once and stored as static class fields.

odata-core/src/main/java/org/apache/olingo/odata2/core/commons/XmlHelper.java
41:      XMLInputFactory factory = XMLInputFactory.newInstance();

odata-core/src/main/java/org/apache/olingo/odata2/core/debug/DebugInfoBody.java
120:      Transformer transformer = TransformerFactory.newInstance().newTransformer();

odata-core/src/main/java/org/apache/olingo/odata2/core/edm/provider/EdmServiceMetadataImplProv.java
75:      XMLStreamWriter xmlStreamWriter = XMLOutputFactory.newInstance().createXMLStreamWriter(writer);

odata-core/src/main/java/org/apache/olingo/odata2/core/ep/AtomEntityProvider.java
110:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
165:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
201:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
228:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
257:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
286:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);
313:      XMLStreamWriter writer = XMLOutputFactory.newInstance().createXMLStreamWriter(outStream, DEFAULT_CHARSET);

odata-core/src/main/java/org/apache/olingo/odata2/core/ep/BasicEntityProvider.java
245:      XMLStreamWriter xmlStreamWriter = XMLOutputFactory.newInstance().createXMLStreamWriter(writer);

odata-core/src/main/java/org/apache/olingo/odata2/core/ep/producer/AtomServiceDocumentProducer.java
60:      XMLStreamWriter xmlStreamWriter = XMLOutputFactory.newInstance().createXMLStreamWriter(writer);

Thanks,
John.