Update to NullAway 0.10.24 and enable experimental JSpecify mode (#1374)

NullAway's JSpecify mode does greater checking around generic types. It
is still experimental, but I will ensure that future fixes in JSpecify
mode won't break WALA's build.

build-logic/src/main/kotlin/com/ibm/wala/gradle/NullAway.gradle.kts

@@ -18,6 +18,7 @@ tasks.withType<JavaCompile>().configureEach {
       error("NullAway")
       errorproneArgs.addAll(
           "-XepOpt:NullAway:AnnotatedPackages=com.ibm.wala",
+          "-XepOpt:NullAway:JSpecifyMode=true",
       )
     }
   }

gradle/libs.versions.toml

@@ -36,7 +36,7 @@ junit-jupiter-engine = { module = "org.junit.jupiter:junit-jupiter-engine" }
 junit-jupiter-params = { module = "org.junit.jupiter:junit-jupiter-params" }
 junit-platform-launcher = { module = "org.junit.platform:junit-platform-launcher" }
 junit-vintage-engine = { module = "org.junit.vintage:junit-vintage-engine" }
-nullaway = "com.uber.nullaway:nullaway:0.10.23"
+nullaway = "com.uber.nullaway:nullaway:0.10.24"
 rhino = "org.mozilla:rhino:1.7.14"
 slf4j-api = "org.slf4j:slf4j-api:2.0.7"
 w3c-css-sac = "org.eclipse.birt.runtime:org.w3c.css.sac:1.3.1.v200903091627"

util/src/main/java/com/ibm/wala/util/graph/GraphSlicer.java

@@ -226,8 +226,7 @@ public void removeNode(E n) {
 
           private final Map<E, Collection<E>> preds = new HashMap<>();
 
-          private Set<E> getConnected(
-              @Nullable E inst, Function<E, Iterator<? extends E>> fconnected) {
+          private Set<E> getConnected(E inst, Function<E, Iterator<? extends E>> fconnected) {
             Set<E> result = new LinkedHashSet<>();
             Set<E> seenInsts = new HashSet<>();
             Set<E> newInsts = Iterator2Collection.toSet(fconnected.apply(inst));
@@ -253,11 +252,11 @@ private Set<E> getConnected(
             return result;
           }
 
-          private void setPredNodes(@Nullable E N) {
+          private void setPredNodes(E N) {
             preds.put(N, getConnected(N, G::getPredNodes));
           }
 
-          private void setSuccNodes(@Nullable E N) {
+          private void setSuccNodes(E N) {
             succs.put(N, getConnected(N, G::getSuccNodes));
           }
 

util/src/main/java/com/ibm/wala/util/io/RtJar.java

@@ -45,8 +45,7 @@ public static void main(String[] args) {
                   try {
                     return new JarFile(object);
                   } catch (IOException e) {
-                    assert false : e.toString();
-                    return null;
+                    throw new RuntimeException(e);
                   }
                 }));