The execution settings
The executionSettings
element is part
of the context
element of the operator model. The executionSettings
element
is after the metrics
element within the context
element.
It describes the execution settings of the operator.
Listing 18: Execution settings type as part of the operator context
Listing 18 gives the basic structure.
<xs:complexTypename="javaOpContextType">
<xs:sequence>
...
<xs:element name="metrics" type="metricsType" minOccurs="0" maxOccurs="1"/>
<xs:element name="executionSettings" type="javaOpExecutionSettingsType"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="javaOpExecutionSettingsType">
<xs:sequence>
<xs:element name="className" type=xs:token"/>
<xs:element name="vmArgs" type="javaOpVMArgsType" minOccurs="0" maxOccurs="1"/>
</xs:sequence>
</xs:complexType>
<xs:complexType name="javaOpVMArgsType">
<xs:sequence>
<xs:element name="vmArg" type="xs:string" minOccurs="0' 'maxOccurs="unbounded"/>
</xs:sequence>
</xs:complexType>
The executionSettings
element
contains two subelements: className
and vmArgs
.
The className
element specifies the name of the class
that represents the operator. The vmArgs
element
specifies the set of JVM arguments that are required by the operator.
Listing 19: Sample execution settings XML segment
Listing 19 gives a sample XML segment for the execution settings.
<executionSettings>
<className>com.acme.streams.MyOp</className>
<vmArgs>
<vmArg>-Dfoo=true</vmArg>
<vmArg>-Xmx32m</vmArg>
</vmArgs>
<executionSettings>
In the example that is
given in Listing 19, the className
element specifies
the namespace qualified class name for the operator. The path to the .jar file
or the directory that contains the class files is specified as part
of the libraryDependencies
element, described in
the next section.