chore: bump maven, maven wrapper and maven plugins (#120)

wrapper: updated by running `./mvnw wrapper:wrapper`
The build now produces bytecode for JDK 17, so the jar produced by this
project no longer works with JDK 8 and JDK 11.

java/.mvn/wrapper/maven-wrapper.properties

@@ -5,14 +5,15 @@
 # to you under the Apache License, Version 2.0 (the
 # "License"); you may not use this file except in compliance
 # with the License.  You may obtain a copy of the License at
-# 
+#
 #   http://www.apache.org/licenses/LICENSE-2.0
-# 
+#
 # Unless required by applicable law or agreed to in writing,
 # software distributed under the License is distributed on an
 # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 # KIND, either express or implied.  See the License for the
 # specific language governing permissions and limitations
 # under the License.
-distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.4/apache-maven-3.8.4-bin.zip
-wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar
+wrapperVersion=3.3.2
+distributionType=only-script
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.9.9/apache-maven-3.9.9-bin.zip

java/README.md

@@ -5,8 +5,8 @@
 To build and run, use:
 > JDK 17 or JDK 21
 
-> [!NOTE]
-> May work with older versions of JDK, but it has not been tested
+> [!WARNING]
+> The build produces bytecode for JDK 17 or newer, so you cannot run the provided jar with older JDK versions.
 
 
 ## Build
@@ -25,7 +25,7 @@ To generate the layout of an existing BPMN file and save the result as a BPMN fi
 java -jar target/bpmn-layout-generator-*-jar-with-dependencies.jar --output=<path_to_output_file> <path_to_input_bpmn_file>
 ```
 If you want to have the resulting layout in an SVG file, pass `--output-type=SVG`   
-Notice that `ASCII` and `SVG` ouput types have been developed to get feedback when running tests i.e. to get a quick preview of the
+Notice that `ASCII` and `SVG` output types have been developed to get feedback when running tests i.e. to get a quick preview of the
 algorithm result. They are not fully implemented and won't probably never be (if you have some interest on that
 topic, feel free to provide a Pull Request)