Contents
This sample shows how to use the TIBCO StreamBase® XML to Tuple and Tuple to XML operators.
The XML to Tuple Java operator converts XML-encoded messages to StreamBase tuples. The operator's input port schema has a single string field that passes an XML-encoded message to the operator. The operator parses the XML message and populates tuple fields corresponding to the elements and attributes found in the message. Each XML message enqueued to the operator results in a single tuple emitted on its output port.
The Tuple to XML Java operator converts StreamBase tuples to XML-encoded messages. Each field in the operator's input port schema populates an element or attribute in the resulting XML message. Each tuple enqueued to the operator results in a single XML message emitted on its output port.
See the description of the operators' Properties views in Using the XML to Tuple Operator and Using the Tuple to XML Operator.
Several sample applications illustrate the use of the XML to Tuple operator. In this first set of samples, the operator parses an XML message and populates the corresponding fields in the output tuple. Each sample application includes a file containing a canned XML message to obviate entering XML strings manually.
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The
xml2tuple-datatypes.sbapp
sample illustrates populating tuple fields from XML elements for a variety of StreamBase data types, including primitive types, lists, and nested tuples. XML attributes are disabled and therefore discarded by the operator. -
The
xml2tuple-attributes.sbapp
sample illustrates two techniques for retrieving XML attributes. The sample's output schema is configured to receive attributes for the following fields:-
Top
-
Top.MyInt
-
Top.MyString
-
Top.MyStringList
-
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The
xml2tuple-fixml.sbapp
sample shows how the operator handles a more complex, hierarchical XML input string that includes element and attribute values, using a FIXML message for its example input. -
The
xml2tuple-xpath.sbapp
sample shows how the operator handles XPath operations to produce sub XML chunks, single elements or lists of data based on the XPath expression.
Two sample applications illustrate the use of the Tuple to XML operator. In this second set of samples, the operator generates and emits an XML message based on the contents of an input tuple.
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In
tuple2xml-datatypes.sbapp
, XML attributes are disabled and are therefore not included in the generated XML message. -
In
tuple2xml-attributes.sbapp
, XML attributes are enabled, and the sample's input schema is configured to generate attributes for the following fields:-
Top
-
Top.Middle
-
-
In the Package Explorer view, in project
sample_xmltuple
, double-click to open the
application.xml2tuple-datatypes.sbapp
-
With the
xml2tuple-datatypes.sbapp
application selected and active, click thebutton. This opens the SB Test/Debug perspective and starts the application.
-
In the Manual Input view, select the
StartRead
stream and click . -
In the Application Output view, observe a tuple dequeued on the
TupleOut
stream in which fields are populated from the contents of the XML message contained inxml2tuple-datatypes.xml
. -
Experiment by entering other values in the
XML
field of theXMLIn
stream, clicking , and observing the resulting output tuples. -
When done, press F9 or click the
Stop Running Application button.
-
Next, open and run the
xml2tuple-attributes.sbapp
application. -
In the Manual Input view, select the
StartRead
stream and click . -
In the Application Output view, observe tuples emitted on the
TupleOut1
andTupleOut2
streams in which fields are populated from the contents of the XML message contained inxml2tuple-attributes.xml
. The attributes in theTupleOut1
tuple appear in subfields whose names match the corresponding XML attribute names, while the attributes in theTupleOut2
tuple appear in subfields of fields named_ATTRIBUTES
. -
Experiment by entering other values in the
XML
field if theXMLIn
stream, clicking , and observing the resulting output tuples. -
When done, press F9 or click the
Stop Running Application button.
-
Next, open and run the
xml2tuple-fixml.sbapp
application. -
In the Manual Input view, select the
StartRead
stream and click . -
This sample's FIXML input string is provided for you in
xml2tuple-fixml.xml
. -
Notice a single tuple emitted on the
TupleOut
stream. Open the tuple's hierarchical levels by clicking the triangles in the Field column. -
When done, press F9 or click the
Stop Running Application button.
-
Next, open and run the
xml2tuple-xpath.sbapp
application. -
In the Manual Input view, select the
ReadFile
stream and click . -
This sample's XML input string is provided for you in
xml2tuple-xpath.xml
. -
Notice a single tuple emitted on the
TupleOut
stream. Open the tuple's hierarchical levels by clicking the triangles in the Field column. Also notice that if a non-list schema type is provided and the XPath expression produces a list of data, only the last XPath node will be used to populate the schema element. If you want all elements then use the list data type. -
When done, press F9 or click the
Stop Running Application button.
-
Open and run the
tuple2xml-datatypes.sbapp
application. -
In the Manual Input view, select the
TupleIn
stream, enter123
in theTop.MyInt
field and click . -
In the Application Output view, observe a single tuple emitted on the
XMLOut
stream in which theXML
field contains<Top><MyInt>123</MyInt><MyTuple></MyTuple></Top>
. -
Experiment by entering other values in various other fields in the Manual Input view, clicking
, and observing the resulting output tuples. -
When done, press F9 or click the
Stop Running Application button.
-
Now run the
tuple2xml-attributes.sbapp
application. -
In the Manual Input view, select the
TupleIn
stream, entermyattrvalue1
andmyattrvalue2
in theTop.s1
andTop.Middle[0].s2
fields, respectively, and click . -
In the Application Output view, observe a single tuple from the
XMLOut1
stream in which theXML
field contains<Top s1="myattrvalue1"><Middle s2="myattrvalue2"></Middle></Top>
. -
When done, press F9 or click the
Stop Running Application button.
In StreamBase Studio, import this sample with the following steps:
-
From the top menu, click
→ . -
Select xmltuple from the Data Constructs and Operators category.
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Click OK.
StreamBase Studio creates a single project for the operator samples.
When you load the sample into StreamBase Studio, Studio copies the sample project's files to your Studio workspace, which is normally part of your home directory, with full access rights.
Important
Load this sample in StreamBase Studio, and thereafter use the Studio workspace copy of the sample to run and test it, even when running from the command prompt.
Using the workspace copy of the sample avoids the permission problems that can occur when trying to work with the initially installed location of the sample. The default workspace location for this sample is:
studio-workspace
/sample_xmltuple
See Default Installation Directories for the location of studio-workspace
on your system.