Various cleanups enabled by bumping minimum Java and Error Prone vers…

…ions (#962)

These warning suppressions and compatibility code are no longed needed
given minimum JDK 11 and Error Prone 2.14.0

jar-infer/jar-infer-lib/src/main/java/com/uber/nullaway/jarinfer/BytecodeAnnotator.java

@@ -249,6 +249,10 @@ private static void copyAndAnnotateJarEntry(
       String manifestText = stringBuilder.toString();
       // Check for evidence of jar signing, note that lines can be split if too long so regex
       // matching line by line will have false negatives.
+      // NOTE: this code only handles the case where the message digest algorithm used when signing
+      // was SHA-256.  Eventually we may need a more robust solution for other digest algorithms.
+      // E.g., on JDK 21, the default message digest algorithm is SHA-384, and this code does not
+      // work for that algorithm (the DIGEST_ENTRY_PATTERN regex is hardcoded for SHA-256)
       String manifestMinusDigests = manifestText.replaceAll(DIGEST_ENTRY_PATTERN, "");
       if (!manifestText.equals(manifestMinusDigests) && !stripJarSignatures) {
         throw new SignedJarException(SIGNED_JAR_ERROR_MESSAGE);

jar-infer/jar-infer-lib/src/test/java/com/uber/nullaway/jarinfer/JarInferTest.java

@@ -27,17 +27,21 @@
 import com.sun.tools.javac.main.Main;
 import java.io.File;
 import java.io.FileInputStream;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.nio.file.FileSystems;
-import java.nio.file.Files;
-import java.nio.file.Paths;
-import java.nio.file.StandardCopyOption;
+import java.security.KeyStore;
+import java.security.KeyStoreException;
 import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.security.UnrecoverableEntryException;
+import java.security.cert.CertificateException;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Set;
+import java.util.zip.ZipFile;
+import jdk.security.jarsigner.JarSigner;
 import org.apache.commons.io.FilenameUtils;
 import org.junit.Assert;
 import org.junit.Before;
@@ -61,11 +65,7 @@ public class JarInferTest {
    * A dummy checker to allow us to use {@link CompilationTestHelper} to compile Java code for
    * testing, as it requires a {@link BugChecker} to run.
    */
-  @BugPattern(
-      name = "DummyChecker",
-      summary = "Dummy checker to use CompilationTestHelper",
-      severity = WARNING)
-  @SuppressWarnings("BugPatternNaming") // remove once we require EP 2.11+
+  @BugPattern(summary = "Dummy checker to use CompilationTestHelper", severity = WARNING)
   public static class DummyChecker extends BugChecker {
     public DummyChecker() {}
   }
@@ -514,32 +514,23 @@ public void testSignedJars() throws Exception {
 
   /** copy the jar at {@code baseJarPath} to a signed jar at {@code signedJarPath} */
   private void copyAndSignJar(String baseJarPath, String signedJarPath)
-      throws IOException, InterruptedException {
-    Files.copy(
-        Paths.get(baseJarPath), Paths.get(signedJarPath), StandardCopyOption.REPLACE_EXISTING);
+      throws CertificateException,
+          KeyStoreException,
+          IOException,
+          NoSuchAlgorithmException,
+          UnrecoverableEntryException {
     String ksPath =
         Thread.currentThread().getContextClassLoader().getResource("testKeyStore.jks").getPath();
-    // A public API for signing jars was added for Java 9+, but there is only an internal API on
-    // Java 8.  And we need the test code to compile on Java 8.  For simplicity and uniformity, we
-    // just run jarsigner as an executable (which slightly slows down test execution)
-    String jarsignerExecutable =
-        String.join(
-            FileSystems.getDefault().getSeparator(),
-            new String[] {System.getenv("JAVA_HOME"), "bin", "jarsigner"});
-    Process process =
-        Runtime.getRuntime()
-            .exec(
-                new String[] {
-                  jarsignerExecutable,
-                  "-keystore",
-                  ksPath,
-                  "-storepass",
-                  "testPassword",
-                  signedJarPath,
-                  "testKeystore"
-                });
-    int exitCode = process.waitFor();
-    Assert.assertEquals("jarsigner process failed", 0, exitCode);
+    var ksPassword = "testPassword".toCharArray();
+    var keystore = KeyStore.getInstance(new File(ksPath), ksPassword);
+    var protParam = new KeyStore.PasswordProtection(ksPassword);
+    var pkEntry = (KeyStore.PrivateKeyEntry) keystore.getEntry("testKeystore", protParam);
+
+    JarSigner signer = new JarSigner.Builder(pkEntry).digestAlgorithm("SHA-256").build();
+    try (ZipFile in = new ZipFile(baseJarPath);
+        FileOutputStream out = new FileOutputStream(signedJarPath)) {
+      signer.sign(in, out);
+    }
   }
 
   private byte[] sha1sum(String path) throws Exception {

nullaway/src/main/java/com/uber/nullaway/NullAway.java

@@ -115,6 +115,7 @@
 import javax.lang.model.element.Element;
 import javax.lang.model.element.ElementKind;
 import javax.lang.model.element.Modifier;
+import javax.lang.model.element.ModuleElement;
 import javax.lang.model.element.NestingKind;
 import javax.lang.model.type.TypeKind;
 import org.checkerframework.nullaway.dataflow.cfg.node.MethodInvocationNode;
@@ -151,12 +152,10 @@
  */
 @AutoService(BugChecker.class)
 @BugPattern(
-    name = "NullAway",
     altNames = {"CheckNullabilityTypes"},
     summary = "Nullability type error.",
     tags = BugPattern.StandardTags.LIKELY_ERROR,
     severity = WARNING)
-@SuppressWarnings("BugPatternNaming") // remove once we require EP 2.11+
 public class NullAway extends BugChecker
     implements BugChecker.MethodInvocationTreeMatcher,
         BugChecker.AssignmentTreeMatcher,
@@ -267,14 +266,6 @@ public Config getConfig() {
    */
   private final Map<ExpressionTree, Nullness> computedNullnessMap = new LinkedHashMap<>();
 
-  /**
-   * Used to check if a symbol represents a module in {@link #matchMemberSelect(MemberSelectTree,
-   * VisitorState)}. We need to use reflection to preserve compatibility with Java 8.
-   *
-   * <p>TODO remove this once NullAway requires JDK 11
-   */
-  @Nullable private final Class<?> moduleElementClass;
-
   /**
    * Error Prone requires us to have an empty constructor for each Plugin, in addition to the
    * constructor taking an ErrorProneFlags object. This constructor should not be used anywhere
@@ -286,7 +277,6 @@ public NullAway() {
     handler = Handlers.buildEmpty();
     nonAnnotatedMethod = this::isMethodUnannotated;
     errorBuilder = new ErrorBuilder(config, "", ImmutableSet.of());
-    moduleElementClass = null;
   }
 
   @Inject // For future Error Prone versions in which checkers are loaded using Guice
@@ -295,14 +285,6 @@ public NullAway(ErrorProneFlags flags) {
     handler = Handlers.buildDefault(config);
     nonAnnotatedMethod = this::isMethodUnannotated;
     errorBuilder = new ErrorBuilder(config, canonicalName(), allNames());
-    Class<?> moduleElementClass = null;
-    try {
-      moduleElementClass =
-          getClass().getClassLoader().loadClass("javax.lang.model.element.ModuleElement");
-    } catch (ClassNotFoundException e) {
-      // can occur pre JDK 11
-    }
-    this.moduleElementClass = moduleElementClass;
   }
 
   private boolean isMethodUnannotated(MethodInvocationNode invocationNode) {
@@ -586,7 +568,7 @@ public Description matchMemberSelect(MemberSelectTree tree, VisitorState state)
     if (symbol == null
         || symbol.getSimpleName().toString().equals("class")
         || symbol.isEnum()
-        || isModuleSymbol(symbol)) {
+        || symbol instanceof ModuleElement) {
       return Description.NO_MATCH;
     }
 
@@ -602,15 +584,6 @@ public Description matchMemberSelect(MemberSelectTree tree, VisitorState state)
     return Description.NO_MATCH;
   }
 
-  /**
-   * Checks if {@code symbol} represents a JDK 9+ module using reflection.
-   *
-   * <p>TODO just check using instanceof once NullAway requires JDK 11
-   */
-  private boolean isModuleSymbol(Symbol symbol) {
-    return moduleElementClass != null && moduleElementClass.isAssignableFrom(symbol.getClass());
-  }
-
   /**
    * Look for @NullMarked or @NullUnmarked annotations at the method level and adjust our scan for
    * annotated code accordingly (fast scan for a fully annotated/unannotated top-level class or

nullaway/src/main/java/com/uber/nullaway/generics/PreservedAnnotationTreeVisitor.java

@@ -266,27 +266,7 @@ public Type createWithBaseTypeAndTypeArgs(Type baseType, List<Type> typeArgs) {
 
   /** The TypeMetadataBuilder to be used for the current JDK version. */
   private static final TypeMetadataBuilder TYPE_METADATA_BUILDER =
-      getVersion() >= 21
+      Runtime.version().feature() >= 21
           ? new JDK21TypeMetadataBuilder()
           : new JDK17AndEarlierTypeMetadataBuilder();
-
-  /**
-   * Utility method to get the current JDK version, that works on Java 8 and above.
-   *
-   * <p>TODO remove this method once we drop support for Java 8
-   *
-   * @return the current JDK version
-   */
-  private static int getVersion() {
-    String version = System.getProperty("java.version");
-    if (version.startsWith("1.")) {
-      version = version.substring(2, 3);
-    } else {
-      int dot = version.indexOf(".");
-      if (dot != -1) {
-        version = version.substring(0, dot);
-      }
-    }
-    return Integer.parseInt(version);
-  }
 }