You are viewing a plain text version of this content. The canonical link for it is here.
Posted to issues@camel.apache.org by "Luca Burgazzoli (JIRA)" <ji...@apache.org> on 2016/12/01 14:03:59 UTC

[jira] [Work started] (CAMEL-10548) Converter from List to String is not found when @EnableAutoConfiguration is used

     [ https://issues.apache.org/jira/browse/CAMEL-10548?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Work on CAMEL-10548 started by Luca Burgazzoli.
-----------------------------------------------
> Converter from List to String is not found when @EnableAutoConfiguration is used
> --------------------------------------------------------------------------------
>
>                 Key: CAMEL-10548
>                 URL: https://issues.apache.org/jira/browse/CAMEL-10548
>             Project: Camel
>          Issue Type: Bug
>          Components: camel-spring-boot
>            Reporter: Luca Burgazzoli
>            Assignee: Luca Burgazzoli
>             Fix For: 2.19.0
>
>
> This very simple spring-boot application :
> {code:java}
> @SpringBootApplication
> public class Application {
>     public static void main(String[] args) {
>         SpringApplication.run(Application.class, args);
>     }
>     @Component
>     public class MyRouteBuilder extends RouteBuilder {
>         @Override
>         public void configure() throws Exception {
>             from("timer:person")
>                 .setBody().constant(Arrays.asList(
>                     new Person("Peter", 25),
>                     new Person("John", 33)
>                 ))
>                 .log("Body is ${body}");
>         }
>     }
>     public static class Person {
>         private String name;
>         private int age;
>         public Person(String name, int age) {
>             this.name = name;
>             this.age = age;
>         }
>         public String getName() {
>             return name;
>         }
>         public void setName(String name) {
>             this.name = name;
>         }
>         public int getAge() {
>             return age;
>         }
>         public void setAge(int age) {
>             this.age = age;
>         }
>         @Override
>         public String toString() {
>             return "Person{" +
>                 "name='" + name + '\'' +
>                 ", age=" + age +
>                 '}';
>         }
>     }
> }
> {code}
> Fails to resolve the simple expression ${body} because of the following exception:
> {code}
> org.apache.camel.TypeConversionException: Error during type conversion from type: java.lang.String to the required type: java.lang.String with value [Person{name='Peter', age=25}, Person{name='John', age=33}] due Failed to convert from type [java.util.Arrays$ArrayList<?>] to type [java.lang.String] for value '[Person{name='Peter', age=25}, Person{name='John', age=33}]'; nested exception is org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.util.Arrays$ArrayList<?>] to type [java.lang.String]
> 	at org.apache.camel.impl.converter.BaseTypeConverterRegistry.createTypeConversionException(BaseTypeConverterRegistry.java:629) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.impl.converter.BaseTypeConverterRegistry.convertTo(BaseTypeConverterRegistry.java:150) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.support.ExpressionAdapter.evaluate(ExpressionAdapter.java:41) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.builder.ExpressionBuilder$75.evaluate(ExpressionBuilder.java:1795) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.support.ExpressionAdapter.evaluate(ExpressionAdapter.java:36) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.LogProcessor.process(LogProcessor.java:53) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.management.InstrumentationProcessor.process(InstrumentationProcessor.java:77) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.RedeliveryErrorHandler.process(RedeliveryErrorHandler.java:542) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197) [camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.Pipeline.process(Pipeline.java:120) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.Pipeline.process(Pipeline.java:83) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.processor.CamelInternalProcessor.process(CamelInternalProcessor.java:197) [camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.component.timer.TimerConsumer.sendTimerExchange(TimerConsumer.java:192) [camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.component.timer.TimerConsumer$1.run(TimerConsumer.java:76) [camel-core-2.18.0.jar:2.18.0]
> 	at java.util.TimerThread.mainLoop(Timer.java:555) [na:1.8.0_112]
> 	at java.util.TimerThread.run(Timer.java:505) [na:1.8.0_112]
> Caused by: org.springframework.core.convert.ConversionFailedException: Failed to convert from type [java.util.Arrays$ArrayList<?>] to type [java.lang.String] for value '[Person{name='Peter', age=25}, Person{name='John', age=33}]'; nested exception is org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.util.Arrays$ArrayList<?>] to type [java.lang.String]
> 	at org.springframework.core.convert.support.ConversionUtils.invokeConverter(ConversionUtils.java:42) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:192) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:176) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.apache.camel.spring.boot.SpringTypeConverter.convertTo(SpringTypeConverter.java:46) ~[camel-spring-boot-2.18.0.jar:2.18.0]
> 	at org.apache.camel.impl.converter.BaseTypeConverterRegistry.doConvertTo(BaseTypeConverterRegistry.java:346) ~[camel-core-2.18.0.jar:2.18.0]
> 	at org.apache.camel.impl.converter.BaseTypeConverterRegistry.convertTo(BaseTypeConverterRegistry.java:133) ~[camel-core-2.18.0.jar:2.18.0]
> 	... 14 common frames omitted
> Caused by: org.springframework.core.convert.ConverterNotFoundException: No converter found capable of converting from type [java.util.Arrays$ArrayList<?>] to type [java.lang.String]
> 	at org.springframework.core.convert.support.GenericConversionService.handleConverterNotFound(GenericConversionService.java:313) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.springframework.core.convert.support.GenericConversionService.convert(GenericConversionService.java:195) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.springframework.core.convert.support.CollectionToStringConverter.convert(CollectionToStringConverter.java:68) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	at org.springframework.core.convert.support.ConversionUtils.invokeConverter(ConversionUtils.java:36) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
> 	... 19 common frames omitted
> {code}
> The root cause is spring failing to find a converter for Person --> String and as the SpringTypeConverter registered by camel-spring-boot is one of the fallback converters used by BaseTypeConverterRegistry, it leads Camel to fail too.
> As today is a Camel TypeConverter fails with an exception while looping over fallback converters, the loops ends and the conversion fails too. It may turn out that the bug is caused by the way camel uses Spring's type converters but it may be good to catch exceptions and try the next converter, [~davsclaus] make sense ?
> A workaround is to create a custom converter for the class:
> {code:java}
>     @Component
>     public class PersonConverter implements Converter<Person, String> {
>         @Override
>         public String convert(Person source) {
>             return source.toString();
>         }
>     }
> {code}



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)