Update spotbugs

Author: simonsteiner1984

.github/workflows/maven.yml

@@ -17,7 +17,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        jdk: ['8', '11', '17', '21']
+        jdk: ['8', '11', '17', '21', '23']
         os: [ubuntu-latest, windows-latest]
 
     steps:
@@ -30,26 +30,6 @@ jobs:
         cache: maven
     - name: Build with Maven
       run: mvn -B package checkstyle:check spotbugs:check --file pom.xml
-      
-  build_nospotbugs:
-    name: Test with Java ${{ matrix.jdk }} ${{ matrix.os }}
-    runs-on: ${{ matrix.os }}
-    strategy:
-      fail-fast: false
-      matrix:
-        jdk: ['23']
-        os: [ubuntu-latest, windows-latest]
-
-    steps:
-    - uses: actions/checkout@v4
-    - name: Set up JDK ${{ matrix.jdk }}
-      uses: actions/setup-java@v3
-      with:
-        java-version: ${{ matrix.jdk }}
-        distribution: 'temurin'
-        cache: maven
-    - name: Build with Maven
-      run: mvn -B package checkstyle:check --file pom.xml      
 
     # Optional: Uploads the full dependency graph to GitHub to improve the quality of Dependabot alerts this repository can receive
     #- name: Update dependency graph

fop-core/src/tools/resources/findbugs/exclusions.xml

@@ -438,6 +438,9 @@
   <Match>
     <Bug pattern="MS_EXPOSE_REP"/>
   </Match>
+  <Match>
+    <Bug pattern="CT_CONSTRUCTOR_THROW,AA_ASSERTION_OF_ARGUMENTS,SING_SINGLETON_GETTER_NOT_SYNCHRONIZED,URF_UNREAD_PUBLIC_OR_PROTECTED_FIELD,UWF_UNWRITTEN_FIELD,UUF_UNUSED_FIELD,UUF_UNUSED_PUBLIC_OR_PROTECTED_FIELD,SING_SINGLETON_HAS_NONPRIVATE_CONSTRUCTOR,UWF_NULL_FIELD,SS_SHOULD_BE_STATIC,PA_PUBLIC_PRIMITIVE_ATTRIBUTE,UWF_UNWRITTEN_PUBLIC_OR_PROTECTED_FIELD,NP_UNWRITTEN_PUBLIC_OR_PROTECTED_FIELD,MC_OVERRIDABLE_METHOD_CALL_IN_READ_OBJECT"/>
+  </Match>  
 
   <!-- Bug in findbugs? -->
   <Match>

fop-sandbox/pom.xml

@@ -110,7 +110,7 @@
         <artifactId>spotbugs-maven-plugin</artifactId>
         <version>${findbugs.plugin.version}</version>
         <configuration>
-          <excludeFilterFile>src/tools/resources/findbugs/exclusions.xml</excludeFilterFile>
+          <excludeFilterFile>../fop-core/src/tools/resources/findbugs/exclusions.xml</excludeFilterFile>
           <effort>Max</effort>
           <threshold>Low</threshold>
         </configuration>

pom.xml

@@ -20,7 +20,7 @@
     <commons.logging.version>1.3.0</commons.logging.version>
     <compiler.plugin.version>3.11.0</compiler.plugin.version>
     <exec.plugin.version>1.4.0</exec.plugin.version>
-    <findbugs.plugin.version>4.7.3.6</findbugs.plugin.version>
+    <findbugs.plugin.version>4.8.4.0</findbugs.plugin.version>
     <jar.plugin.version>3.1.1</jar.plugin.version>
     <java.version>8</java.version>
     <junit.version>4.13.2</junit.version>