About config file

Hello i have a problem with my config manager when i compile my plugini have this error
C:\Users\maxime\Desktop\sauvgarde\Nouveau dossier\plugn work\Copy of Sponge\src\main\java\MainLootCase.java:[51,76] error: lambda expressions are not supported in -source 1.5
and at this line i have this
configManager.setup(defaultConfig, configLoader, getLogger(), config-> {

You’re telling the Java compiler that the source is written in Java 5, which is definitely not going to work because Sponge requires Java 8 to compile and run.

You need to change the source (and possibly target) compatibility level.
Is this only in the IDE or does this happen when running a build task (e.g. with Gradle)?

The problem is when i run a build task
I use eclipse and i have jdk 1.8

Then you need to specify to gradle that the source is in 1.8.

sourceCompatibility = 1.8

how i can do this on maven project ?

C,est comme sa.

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.3</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

yes but i have this in my pom.xml

[code]
4.0.0
terrainwax
LootCase
0.0.1-WIP
terrainwax plugin
plugin sponge of terrainwax


sponge-maven-repo
Sponge maven repo
http://repo.spongepowered.org/maven

true


true


org.spongepowered spongeapi 3.0.0 provided [/code] no build no plugin

Put it between version and repository.

Please use a [code][/code] block to provide config files and code. It is easier to read and prevents <xml><tags /></xml> from being parsed (or attempted to parse) by discourse.