No grammar constraints (dtd or xml schema) referenced in the document.

Question

Problem :

Currently I am trying to learn the Apache Maven. I have tried to write below code in Eclipse but it is giving below error to me:

Error Message:

“No grammar constraints (DTD or XML Schema) referenced in the document”

My Code :

<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0
http://maven.apache.org/xsd/maven-4.0.0.xsd">

<modelVersion>4.0.0</modelVersion>
<groupId>br.gov.mdic</groupId>
<artifactId>Offset</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>

<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

<build>
<plugins>
    <plugin>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.0</version>
        <configuration>
            <source>1.8</source>
            <target>1.8</target>
        </configuration>
    </plugin>
</plugins>

Answer 1

I have faced this error earlier and I fixed it using below procedure

In your eclipse IDE to avoid the below message

 "No grammar constraints (dtd or xml schema) detected for the document."

I added the xsd schema file to a xml catalog under below path

"Go to Window \ preferences \ xml \ xml catalog \ User specified entries".

Then you need to click on "Add" button on your right.

<?xml version="1.0" encoding="UTF-8"?>
<HolidayRequest xmlns="http://mycompany.com/hr/schemas">
    <Holiday>
        <StartDate>2006-07-03</StartDate>
        <EndDate>2006-07-07</EndDate>
    </Holiday>
    <Employee>
        <Number>42</Number>
        <FirstName>Arjen</FirstName>
        <LastName>Poutsma</LastName>
    </Employee>
</HolidayRequest>

From above xml I had generated and then saved the xsd under below location: /home/my_user/xsd/my_xsd.xsd

As Location: /home/my_user/xsd/my_xsd.xsd

As key type: Namespace name

As key: http://mycompany.com/hr/schemas

After doing above steps you can close and then reopen the xml file and do some changes to violate the schema, you should be notified