[java] Why am I getting Unknown error in line 1 of pom.xml?

Getting unknown error at Line 1 in pom.xml in Eclipse IDE. It was working fine till yesterday, but all of a sudden after updating my project from master and after fixing merge conflicts getting "Unknown error" in pom.xml. Except me, none of my teammates are facing this issue. I also changed the workspace, deleted cache but still no luck.

I am using the h2 database for this project, in spite of inserting values in data.sql, it is not picking up any values and inserting into h2 DB tables. Before this issue, it was working fine. I feel its due to the issue in pom.xml, I am not sure though. Please help

I deleted the existing project and took the latest code from master. After that deleted .m2 folder under users including the repository folder. I did update project and enabled Forced update of snapshots/releases, maven clean and maven build. But nothing helps.

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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>com.abc.roster</groupId>
    <artifactId>spring-boot-roster-app</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>spring-boot-roster-app</name>
    <description>Demo project for Spring Boot Roster</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.0.BUILD-SNAPSHOT</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
        <!-- <start-class>com.infosys.roster.SpringBootRosterAppApplication</start-class> -->
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <!--encryption lib -->
        <dependency>
            <groupId>org.jasypt</groupId>
            <artifactId>jasypt</artifactId>
            <version>1.9.2</version>
        </dependency>

        <dependency>
            <groupId>org.jasypt</groupId>
            <artifactId>jasypt-springsecurity3</artifactId>
            <version>1.9.0</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-rest</artifactId>
        </dependency>

        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <scope>runtime</scope>

        </dependency>


<!--        <dependency> -->
<!--         <groupId>org.hibernate</groupId> -->
<!--         <artifactId>hibernate-core</artifactId> -->
<!--         <version>5.2.10.Final</version> -->
<!--   </dependency> -->

        <!-- <dependency> -->
        <!-- <groupId>io.springfox</groupId> -->
        <!-- <artifactId>springfox-swagger2</artifactId> -->
        <!-- <version>2.7.0</version> -->
        <!-- <scope>compile</scope> -->
        <!-- </dependency> -->


        <!-- <dependency> -->
        <!-- <groupId>io.springfox</groupId> -->
        <!-- <artifactId>springfox-swagger-ui</artifactId> -->
        <!-- <version>2.7.0</version> -->
        <!-- <scope>compile</scope> -->
        <!-- </dependency> -->

        <!-- <dependency> -->
        <!-- <groupId>io.springfox</groupId> -->
        <!-- <artifactId>springfox-data-rest</artifactId> -->
        <!-- <version>2.7.0</version> -->
        <!-- </dependency> -->
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

    <repositories>
        <repository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </repository>
        <repository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
        </repository>
    </repositories>
    <pluginRepositories>
        <pluginRepository>
            <id>spring-snapshots</id>
            <name>Spring Snapshots</name>
            <url>https://repo.spring.io/snapshot</url>
            <snapshots>
                <enabled>true</enabled>
            </snapshots>
        </pluginRepository>
        <pluginRepository>
            <id>spring-milestones</id>
            <name>Spring Milestones</name>
            <url>https://repo.spring.io/milestone</url>
        </pluginRepository>
    </pluginRepositories>

</project> 

application.properties

server.port=
spring.h2.console.path=/h2
spring.h2.console.enabled=true

spring.datasource.url=


spring.datasource.username=
spring.datasource.password=
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.platform=h2
spring.datasource.initialization-mode=always

spring.jpa.hibernate.ddl-auto=update
spring.datasource.continue-on-error=true

spring.jpa.show-sql=true
spring.jpa.properties.hibernate.format_sql=false

spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.H2Dialect

Should remove unknown error in pom.xml and also I must be able to populate values in H2 db.

For me I changed in the parent tag of the pom.xml and it solved it change 2.1.5 to 2.1.4 then Maven-> Update Project

Add 3.1.1 in to properties like below than fix issue

<properties>
        <java.version>1.8</java.version>
        <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version>
</properties>

Just Update Project => right click => Maven=> Update Project

As per the suggestion from @Shravani, in my pom.xml file, I changed my version number in the area from this:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.5.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

to this:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.4.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

I then right clicked on the project and did a 'Maven -> Update project...'. This made the problem go away for me.

There is a bug about Eclipse and spring-boot-starter-parent 2.1.5

"if the maven packaging attribute is war then no problem.The problem is in jar type." So you can also fix this problem by changing packaging type.

<packaging>war</packaging>

You must to upgrade the m2e connector. It's a known bug, but there is a solution:

1. Into Eclipse click "Help" > "Install new Software..."

2. Appears a window. In the "Install" window:

   2a. Into the input box "Work with", enter next site location and press Enter https://download.eclipse.org/m2e-wtp/releases/1.4/

   2b. Appears a lot of information into "Name" input Box. Select all the items

   2c. Click "Next" Button.

Finish the installation and restart Eclipse.

I updated spring tool suits by going help > check for update.

For me, changing pom.xml for SpringBoot 2 project from 2.1.6.RELEASE

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.REL`enter code here`EASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

to 2.1.4.RELEASE verified and works

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

same problem for me, original code from spring starter demo gives unknown error on line 1:

<?xml version="1.0" encoding="UTF-8"?>
<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>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.6.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
...

Changing just the version of 2.1.6.RELEASE to 2.1.4.RELEASE fixes the problem.

While I cannot reproduce your error (as none of your team mates can either), I have a suggestion, that might help you.

Have you heard of the Byte Order Mark? As it appears on line 1 it is a likely candidate for your troubles. Maybe you changed a setting somewhere that somehow leads to the error. This quote from the Wikipedia article is particularly relevant I think:

BOM use is optional. Its presence interferes with the use of UTF-8 by software that does not expect non-ASCII bytes at the start of a file but that could otherwise handle the text stream.

For me I changed in the parent tag of the pom.xml and it solved it change 2.1.5 to 2.1.4 then Maven-> Update Project. its worked for me also.

I was getting same error in Version 3. It worked after upgrading STS to latest version: 4.5.1.RELEASE. No change in code or configuration in latest STS was required.

Got this error on eclipse IDE version 4.10, Spring boot 2.2.0.M4, changed the Spring boot version to 2.2.0.M2 (after many other solutions recommended and it solved the error). Maybe something missing or broken in the latest version of Spring boot starter project module maven POM.

In my pom.xml file I had to downgrade the version from 2.1.6.RELEASE for spring-boot-starter-parent artifact to 2.1.4.RELEASE

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

to be changed to

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
</parent>

And that weird Unknown error disappeared

You just need a latest Eclipse or Spring tool suite 4.5 and above.Nothing else.refresh project and it works

whenever you facing this type of error simply change the Release version just like In my case it is showing Error in 2.2.7 I changed to 2.2.6

Problem:

<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.7.RELEASE</version>

Solution:

<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.6.RELEASE</version>

Add <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version> in property tag

problem resolve

https://medium.com/@saannjaay/unknown-error-in-pom-xml-66fb2414991b

Simply add below maven jar version in properties tag in pom.xml, <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version>

Then follow below steps,

Step 1: mvn clean

Step 2 : update project

Problem solved for me! You should also try this :)

Following actions worked for me.

1.Go to Project in toolbar -> Unchecked "Build Automatically"

2.In POM File,Downgrade the spring-boot version to 2.1.4 RELEASE.

3.Right Click on Project name -> Select Maven -> Click on "Update Project". ->OK Wait till all the maven dependency to get downloaded(Need internet).