Spring Integration Kafka Configuration - Errors in Eclipse - spring-integration

Question

I am using Eclipse as the IDE. I have a very basic config XML file that does not validate and hence prevents Eclipse from running anything. What am I missing?
Here's the validation errors (I see the in problems view):
Here's my config xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:int="http://www.springframework.org/schema/integration"
xmlns:int-kafka="http://www.springframework.org/schema/integration/kafka"
xmlns:task="http://www.springframework.org/schema/task"
xsi:schemaLocation="http://www.springframework.org/schema/integration/kafka http://www.springframework.org/schema/integration/kafka/spring-integration-kafka.xsd
http://www.springframework.org/schema/integration http://www.springframework.org/schema/integration/spring-integration.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task.xsd">
<int:channel id="inputToKafka" />
<int-kafka:outbound-channel-adapter
id="kafkaOutboundChannelAdapter" kafka-template="template"
auto-startup="false" channel="inputToKafka" topic="replicated-topic-1"
message-key-expression="'bar'" partition-id-expression="2">
</int-kafka:outbound-channel-adapter>
<bean id="template" class="org.springframework.kafka.core.KafkaTemplate">
<constructor-arg>
<bean class="org.springframework.kafka.core.DefaultKafkaProducerFactory">
<constructor-arg>
<map>
<entry key="bootstrap.servers" value="192.168.33.21:9092,192.168.33.22:9092,192.168.33.23:9092" />
</map>
</constructor-arg>
</bean>
</constructor-arg>
</bean>
<int-kafka:message-driven-channel-adapter
id="kafkaListener"
listener-container="listenerContainer"
auto-startup="false"
phase="100"
send-timeout="5000"
channel="nullChannel"
error-channel="errorChannel" />
<bean id="listenerContainer" class="org.springframework.kafka.listener.KafkaMessageListenerContainer">
<constructor-arg>
<bean class="org.springframework.kafka.core.DefaultKafkaConsumerFactory">
<constructor-arg>
<map>
<entry key="bootstrap.servers" value="192.168.33.21:9092,192.168.33.22:9092,192.168.33.23:9092" />
</map>
</constructor-arg>
</bean>
</constructor-arg>
<constructor-arg name="topics" value="replicated-topic-1" />
</bean>
</beans>

Answer 1

If these are just bogus errors and the app runs ok, it simply means you are resolving to the online version of the spring-integration-core schema here. See the IMPORTANT note at the top of that schema as to why it is not the current version.
You can resolve that by using a spring-aware eclipse (e.g. STS or the Spring IDE plugin) and set spring nature on the project so the schema is resolved properly, from the class path, instead of the internet.
Or you can go to the XML Catalog in eclipse preferences and configure the schema mapping to properly point to the 4.3 version of the schema.
If it's truly a runtime problem (app won't run), then it means you have an incorrect version of spring-integration-core on the classpath - you should use maven or gradle to pull in the correct version transitively. If you are manually building the project class path, you need spring-integration-core version 4.3.2 or later (current version is 4.3.4).