将非Maven项目转换为Maven

Question

I am trying to convert and old non-maven java NetBeans project to a maven project. The existing project has 36 libraries.

What I did

1. I outputted the library folder content to a file and got the list of all the jars.
2. I searched for the jar in maven repo and added the specific version as dependency in pom

The Result

The new maven project now has some new jars which the old one didn't have, probably they are added because they were the dependencies of the ones I added.

My Questions

1. If the extra jars that are added in the "Dependencies" section are required by the jars that I added, how was the old project running? ie without those jars included?
2. Some of the jars in the old project I believe were the dependencies of other jars. This I figured out when I added a jar and it added another jar by itself which I was about to add. So how do I figure out which jar is the dependency of which one so I don't explicitly specify that one in my pom? or so I could add them in sequence.

EDIT:

Thanks to @SubOptimal, i was able to check the graph, but here is what I get:

On the left is the old project opened with all the libraries, on the right, is the newly maven converted project's graph opened. Now you can see the library is the same "axis2-kernel-1.6.1.jar". On the left, the old project doesn't have the geronimo-ws-metadata_2.0_spec which is shown as a dependency of the axis2 library.

Now my question is the same, how was the old project working, is this an optional dependency?

Answer 1

The new dependencies might be there because of different library version in the old non-maven project and the new maven project.

Assume the non-maven project would have used JUnit in version 3.8.

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>sub.optimal</groupId>
    <artifactId>foo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
</project>

in this example you would have only JUnit as dependency

mvn dependency:tree

output

[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ suboptimal ---
[INFO] com.example:suboptimal:jar:0.0.1-SNAPSHOT
[INFO] \- junit:junit:jar:3.8:test

If you now in the maven project would use version 4.12 (instead of the previous 3.8) you would see following dependencies (after changing the version number in the pom.xml )

<groupId>junit</groupId>
    <artifactId>junit</artifactId>
<version>4.12</version>

output would be

[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ suboptimal ---
[INFO] com.example:suboptimal:jar:0.0.1-SNAPSHOT
[INFO] \- junit:junit:jar:4.12:test
[INFO]    \- org.hamcrest:hamcrest-core:jar:1.3:test

For the shown dependency junit:junit:jar:4.12:test the test means it's not a runtime dependency. It's need to run the provided tests.

In Netbeans you would see now both as a test dependency

There is another way to show the dependencies directly in Netbeans. When you open the pom.xml click on Graph and only for the first time after you open it on Show Graph .

You get a visual dependency tree

edit: You have not yet said what your old project uses. But find one example for the axis2 kernel below.

When your new project add following dependency

<dependency>
    <groupId>org.apache.axis2</groupId>
    <artifactId>axis2-kernel</artifactId>
    <version>1.6.1</version>
</dependency>

listing the dependencies with mvn dependency:tree reveals following compile time dependencies (needed also for the runtime, see Maven dependency scopes )

[INFO] \- org.apache.axis2:axis2-kernel:jar:1.6.1:compile
[INFO]    +- org.apache.ws.commons.axiom:axiom-api:jar:1.2.12:compile
[INFO]    |  +- org.apache.geronimo.specs:geronimo-activation_1.1_spec:jar:1.0.2:compile
[INFO]    |  +- org.apache.geronimo.specs:geronimo-javamail_1.4_spec:jar:1.6:compile
[INFO]    |  +- jaxen:jaxen:jar:1.1.1:compile
[INFO]    |  \- org.apache.geronimo.specs:geronimo-stax-api_1.0_spec:jar:1.0.1:compile
[INFO]    +- org.apache.ws.commons.axiom:axiom-impl:jar:1.2.12:compile
[INFO]    |  \- org.codehaus.woodstox:wstx-asl:jar:3.2.9:compile
[INFO]    +- org.apache.geronimo.specs:geronimo-ws-metadata_2.0_spec:jar:1.1.2:compile
[INFO]    +- org.apache.geronimo.specs:geronimo-jta_1.1_spec:jar:1.1:compile
[INFO]    +- javax.servlet:servlet-api:jar:2.3:compile
[INFO]    +- commons-httpclient:commons-httpclient:jar:3.1:compile
[INFO]    |  \- commons-codec:commons-codec:jar:1.2:compile
[INFO]    +- commons-fileupload:commons-fileupload:jar:1.2:compile
[INFO]    +- wsdl4j:wsdl4j:jar:1.6.2:compile
[INFO]    +- org.apache.ws.commons.schema:XmlSchema:jar:1.4.7:compile
[INFO]    +- org.apache.neethi:neethi:jar:3.0.1:compile
[INFO]    +- org.apache.woden:woden-api:jar:1.0M9:compile
[INFO]    +- org.apache.woden:woden-impl-dom:jar:1.0M9:compile
[INFO]    |  \- org.apache.woden:woden-impl-commons:jar:1.0M9:compile
[INFO]    +- commons-logging:commons-logging:jar:1.1.1:compile
[INFO]    \- javax.ws.rs:jsr311-api:jar:1.0:compile

So why it looks now your old project was not needing them? Assuming that your old project uses the axis2.war file (extracted from axis2-1.6.1-war.zip ). The dependencies are embedded.

jar -tf axis2.war | grep geronimo-ws-metadata

output

WEB-INF/lib/geronimo-ws-metadata-LICENSE.txt
WEB-INF/lib/geronimo-ws-metadata_2.0_spec-1.1.2.jar