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Spring Expression Language docs

This commit is contained in:
Mark Pollack 2009-04-07 04:45:05 +00:00
parent 1f00e639e0
commit 5f5bee1022
1 changed files with 13 additions and 8 deletions
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21
spring-framework-reference/src/expressions.xml
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@ -95,6 +95,10 @@
<para>User defined functions</para> <para>User defined functions</para>
</listitem> </listitem>
<listitem>
<para>List projections</para>
</listitem>
<listitem> <listitem>
<para>Templated expressions</para> <para>Templated expressions</para>
</listitem> </listitem>
@ -564,7 +568,7 @@ boolean falseValue = parser.parseExpression(expression).getValue(societyContext,
supported are modulus (%) and exponential power (^). Standard operator supported are modulus (%) and exponential power (^). Standard operator
precedence is enforced. These operators are demonstrated below </para> precedence is enforced. These operators are demonstrated below </para>
<para><programlisting>// Addition <para><programlisting language="java">// Addition
int two = parser.parseExpression("1 + 1").getValue(Integer.class); // 2 int two = parser.parseExpression("1 + 1").getValue(Integer.class); // 2
String testString = parser.parseExpression("'test' + ' ' + 'string'").getValue(String.class); // 'test string' String testString = parser.parseExpression("'test' + ' ' + 'string'").getValue(String.class); // 'test string'
@ -605,7 +609,7 @@ int minusTwentyOne = parser.parseExpression("1+2-3*8").getValue(Integer.class);
This would typically be done within a call to SetValue but can also be This would typically be done within a call to SetValue but can also be
done inside a call to GetValue </para> done inside a call to GetValue </para>
<programlisting>Inventor inventor = new Inventor(); <programlisting language="java">Inventor inventor = new Inventor();
StandardEvaluationContext inventorContext = new StandardEvaluationContext(); StandardEvaluationContext inventorContext = new StandardEvaluationContext();
inventorContext.setRootObject(inventor); inventorContext.setRootObject(inventor);
@ -627,7 +631,7 @@ String aleks = parser.parseExpression("Name = 'Alexandar Seovic'").getValue(inve
java.lang.Class (the 'type'). Static methods are invoked using this java.lang.Class (the 'type'). Static methods are invoked using this
operator as well</para> operator as well</para>
<programlisting>Class dateClass = parser.parseExpression("T(java.util.Date)").getValue(Class.class); <programlisting language="java">Class dateClass = parser.parseExpression("T(java.util.Date)").getValue(Class.class);
boolean isEqual = parser.parseExpression("T(java.math.RoundingMode).CEILING &lt; T(java.math.RoundingMode).FLOOR").getValue(Boolean.class); boolean isEqual = parser.parseExpression("T(java.math.RoundingMode).CEILING &lt; T(java.math.RoundingMode).FLOOR").getValue(Boolean.class);
@ -641,7 +645,7 @@ boolean isEqual = parser.parseExpression("T(java.math.RoundingMode).CEILING &lt;
qualified classname should be used for all but the primitive type and qualified classname should be used for all but the primitive type and
String (where int, float, etc, can be used).</para> String (where int, float, etc, can be used).</para>
<programlisting>Inventor einstein = <programlisting language="java">Inventor einstein =
parser.parseExpression("new org.spring.samples.spel.inventor.Inventor('Albert Einstein', 'German')").getValue(Inventor.class); parser.parseExpression("new org.spring.samples.spel.inventor.Inventor('Albert Einstein', 'German')").getValue(Inventor.class);
//create new inventor instance within add method of List //create new inventor instance within add method of List
@ -656,7 +660,7 @@ parser.parseExpression("Members.add(new org.spring.samples.spel.inventor.Invento
#variableName. Variables are set using the method setVariable on the #variableName. Variables are set using the method setVariable on the
StandardEvaluationContext. </para> StandardEvaluationContext. </para>
<programlisting>Inventor tesla = new Inventor("Nikola Tesla", "Serbian"); <programlisting language="java">Inventor tesla = new Inventor("Nikola Tesla", "Serbian");
StandardEvaluationContext context = new StandardEvaluationContext(); StandardEvaluationContext context = new StandardEvaluationContext();
context.setVariable("newName", "Mike Tesla"); context.setVariable("newName", "Mike Tesla");
context.setRootObject(tesla); context.setRootObject(tesla);
@ -689,13 +693,14 @@ System.out.println(tesla.getName()) // "Mike Tesla"</programlisting>
<para>In this case, the boolean false results in returning the string <para>In this case, the boolean false results in returning the string
value 'falseExp'. A less artificial example is shown below.</para> value 'falseExp'. A less artificial example is shown below.</para>
<programlisting>parser.parseExpression("Name").setValue(societyContext, "IEEE"); <programlisting language="java">parser.parseExpression("Name").setValue(societyContext, "IEEE");
societyContext.setVariable("queryName", "Nikola Tesla"); societyContext.setVariable("queryName", "Nikola Tesla");
expression = "isMember(#queryName)? #queryName + ' is a member of the ' " + expression = "isMember(#queryName)? #queryName + ' is a member of the ' " +
"+ Name + ' Society' : #queryName + ' is not a member of the ' + Name + ' Society'"; "+ Name + ' Society' : #queryName + ' is not a member of the ' + Name + ' Society'";
String queryResultString = parser.parseExpression(expression).getValue(societyContext, String.class);</programlisting> String queryResultString = parser.parseExpression(expression).getValue(societyContext, String.class);
// queryResultString = "Nikola Tesla is a member of the IEEE Society"</programlisting>
</section> </section>
<section> <section>
@ -711,7 +716,7 @@ String queryResultString = parser.parseExpression(expression).getValue(societyCo
original element list. For example, selection would allow us to easily original element list. For example, selection would allow us to easily
get a list of Serbian inventors:</para> get a list of Serbian inventors:</para>
<programlisting>List&lt;Inventor&gt; list = (List&lt;Inventor&gt;) parser.parseExpression("Members.?{Nationality == 'Serbian'}").getValue(societyContext);</programlisting> <programlisting language="java">List&lt;Inventor&gt; list = (List&lt;Inventor&gt;) parser.parseExpression("Members.?{Nationality == 'Serbian'}").getValue(societyContext);</programlisting>
</section> </section>
<section> <section>