SpringCloud/spring-cloud-sleuth
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buildmaster
2019-02-07 12:19:05 +00:00
parent 10898a75c3
commit 7fa8a80173
3 changed files with 30 additions and 24 deletions
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18
spring-cloud-sleuth.xml
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@@ -1440,10 +1440,10 @@ void testMethod4();</programlisting>
<simpara>If you provide the value in the annotation (either directly or by setting the <literal>name</literal> parameter), the created span has the provided value as the name.</simpara>
<programlisting language="java" linenumbering="unnumbered">// method declaration
@NewSpan(name = "customNameOnTestMethod5")
void testMethod5();
void testMethod5(@SpanTag("testTag") String param);
// and method execution
this.testBean.testMethod5();</programlisting>
this.testBean.testMethod5("test");</programlisting>
<simpara>You can combine both the name and a tag. Let&#8217;s focus on the latter.
In this case, the value of the annotated method&#8217;s parameter runtime value becomes the value of the tag.
In our sample, the tag key is <literal>testTag</literal>, and the tag value is <literal>test</literal>.</simpara>
@@ -1460,10 +1460,10 @@ concrete one wins (in this case <literal>customNameOnTestMethod3</literal> is se
<simpara>If you want to add tags and annotations to an existing span, you can use the <literal>@ContinueSpan</literal> annotation, as shown in the following example:</simpara>
<programlisting language="java" linenumbering="unnumbered">// method declaration
@ContinueSpan(log = "testMethod11")
void testMethod11();
void testMethod11(@SpanTag("testTag11") String param);
// method execution
this.testBean.testMethod11();
this.testBean.testMethod11("test");
this.testBean.testMethod13();</programlisting>
<simpara>(Note that, in contrast with the <literal>@NewSpan</literal> annotation ,you can also add logs with the <literal>log</literal> parameter.)</simpara>
<simpara>That way, the span gets continued and:</simpara>
@@ -1503,12 +1503,13 @@ The default implementation uses SPEL expression resolution.
Its class name has to be passed as the value of the <literal>resolver</literal> attribute.</simpara>
<simpara>Consider the following annotated method:</simpara>
<programlisting language="java" linenumbering="unnumbered">@NewSpan
public void getAnnotationForTagValueResolver() {
public void getAnnotationForTagValueResolver(
@SpanTag(key = "test", resolver = TagValueResolver.class) String test) {
}</programlisting>
<simpara>Now further consider the following <literal>TagValueResolver</literal> bean implementation:</simpara>
<programlisting language="java" linenumbering="unnumbered">@Bean(name = "myCustomTagValueResolver")
public TagValueResolver tagValueResolver() {
return () -&gt; "Value from myCustomTagValueResolver";
return parameter -&gt; "Value from myCustomTagValueResolver";
}</programlisting>
<simpara>The two preceding examples lead to setting a tag value equal to <literal>Value from myCustomTagValueResolver</literal>.</simpara>
</section>
@@ -1516,7 +1517,8 @@ public TagValueResolver tagValueResolver() {
<title>Resolving Expressions for a Value</title>
<simpara>Consider the following annotated method:</simpara>
<programlisting language="java" linenumbering="unnumbered">@NewSpan
public void getAnnotationForTagValueExpression() {
public void getAnnotationForTagValueExpression(
@SpanTag(key = "test", expression = "'hello' + ' characters'") String test) {
}</programlisting>
<simpara>No custom implementation of a <literal>TagValueExpressionResolver</literal> leads to evaluation of the SPEL expression, and a tag with a value of <literal>4 characters</literal> is set on the span.
If you want to use some other expression resolution mechanism, you can create your own implementation of the bean.</simpara>
@@ -1525,7 +1527,7 @@ If you want to use some other expression resolution mechanism, you can create yo
<title>Using the <literal>toString()</literal> method</title>
<simpara>Consider the following annotated method:</simpara>
<programlisting language="java" linenumbering="unnumbered">@NewSpan
public void getAnnotationForArgumentToString() {
public void getAnnotationForArgumentToString(@SpanTag("test") Long param) {
}</programlisting>
<simpara>Running the preceding method with a value of <literal>15</literal> leads to setting a tag with a String value of <literal>"15"</literal>.</simpara>
</section>