Enable Nullaway

build.gradle

@@ -31,6 +31,7 @@ apply plugin: 'com.palantir.consistent-versions'
 version System.env.CIRCLE_TAG ?: gitVersion()
 
 allprojects {
+    apply plugin: 'com.palantir.baseline-null-away'
     apply plugin: 'com.palantir.java-format'
     apply plugin: 'com.palantir.jakarta-package-alignment'
     group = 'com.palantir.javaformat'

changelog/@unreleased/pr-988.v2.yml

@@ -0,0 +1,5 @@
+type: improvement
+improvement:
+  description: Enable Nullaway
+  links:
+  - https://github.com/palantir/palantir-java-format/pull/988

eclipse_plugin/src/main/java/com/palantir/javaformat/java/PalantirJavaFormatter.java

@@ -19,6 +19,7 @@
 import com.palantir.javaformat.java.SnippetFormatter.SnippetKind;
 import java.util.ArrayList;
 import java.util.List;
+import javax.annotation.Nullable;
 import org.eclipse.jdt.core.dom.ASTParser;
 import org.eclipse.jdt.core.formatter.CodeFormatter;
 import org.eclipse.jface.text.IRegion;
@@ -32,13 +33,15 @@ public class PalantirJavaFormatter extends CodeFormatter {
 
     private static final int INDENTATION_SIZE = 4;
 
+    @Nullable
     @Override
     public TextEdit format(
             int kind, String source, int offset, int length, int indentationLevel, String _lineSeparator) {
         IRegion[] regions = new IRegion[] {new Region(offset, length)};
         return formatInternal(kind, source, regions, indentationLevel);
     }
 
+    @Nullable
     @Override
     public TextEdit format(int kind, String source, IRegion[] regions, int indentationLevel, String _lineSeparator) {
         return formatInternal(kind, source, regions, indentationLevel);
@@ -57,6 +60,7 @@ public String createIndentationString(int indentationLevel) {
     }
 
     /** Runs the Google Java formatter on the given source, with only the given ranges specified. */
+    @Nullable
     private TextEdit formatInternal(int kind, String source, IRegion[] regions, int initialIndent) {
         try {
             boolean includeComments = (kind & CodeFormatter.F_INCLUDE_COMMENTS) == CodeFormatter.F_INCLUDE_COMMENTS;

palantir-java-format/src/main/java/com/palantir/javaformat/java/CommandLineOptionsParser.java

@@ -28,6 +28,7 @@
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
+import javax.annotation.Nullable;
 
 /** A parser for {@link CommandLineOptions}. */
 final class CommandLineOptionsParser {
@@ -50,7 +51,7 @@ static CommandLineOptions parse(Iterable<String> options) {
                 break;
             }
             String flag;
-            String value;
+            @Nullable String value;
             int idx = option.indexOf('=');
             if (idx >= 0) {
                 flag = option.substring(0, idx);
@@ -151,7 +152,7 @@ private static Integer parseInteger(Iterator<String> it, String flag, String val
         }
     }
 
-    private static String getValue(String flag, Iterator<String> it, String value) {
+    private static String getValue(String flag, Iterator<String> it, @Nullable String value) {
         if (value != null) {
             return value;
         }

palantir-java-format/src/main/java/com/palantir/javaformat/java/JavaCommentsHelper.java

@@ -24,12 +24,15 @@
 import java.util.List;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
+import javax.annotation.Nullable;
 
 /** {@code JavaCommentsHelper} extends {@link CommentsHelper} to rewrite Java comments. */
 public final class JavaCommentsHelper implements CommentsHelper {
 
     private final String lineSeparator;
     private final JavaFormatterOptions options;
+
+    @Nullable
     private final JavadocFormatter javadocFormatter;
 
     public JavaCommentsHelper(String lineSeparator, JavaFormatterOptions options) {

palantir-java-format/src/main/java/com/palantir/javaformat/java/Main.java

@@ -28,6 +28,8 @@
 import java.util.Arrays;
 import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Optional;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
@@ -130,7 +132,7 @@ private int formatFiles(CommandLineOptions parameters, JavaFormatterOptions opti
             }
         }
 
-        for (Map.Entry<Path, Future<String>> result : results.entrySet()) {
+        for (Entry<Path, Future<String>> result : results.entrySet()) {
             Path path = result.getKey();
             String formatted;
             try {
@@ -145,8 +147,11 @@ private int formatFiles(CommandLineOptions parameters, JavaFormatterOptions opti
                         errWriter.println(path + ":" + diagnostic.toString());
                     }
                 } else {
-                    errWriter.println(path + ": error: " + e.getCause().getMessage());
-                    e.getCause().printStackTrace(errWriter);
+                    errWriter.println(path + ": error: "
+                            + Optional.ofNullable(e.getCause())
+                                    .map(Throwable::getMessage)
+                                    .orElse("null"));
+                    Optional.ofNullable(e.getCause()).ifPresent(cause -> cause.printStackTrace(errWriter));
                 }
                 allOk = false;
                 continue;
@@ -215,10 +220,10 @@ public static CommandLineOptions processArgs(String... args) throws UsageExcepti
         try {
             parameters = CommandLineOptionsParser.parse(Arrays.asList(args));
         } catch (IllegalArgumentException e) {
-            throw new UsageException(e.getMessage());
+            throw new UsageException(Optional.ofNullable(e.getMessage()).orElse("null"));
         } catch (Throwable t) {
             t.printStackTrace();
-            throw new UsageException(t.getMessage());
+            throw new UsageException(Optional.ofNullable(t.getMessage()).orElse("null"));
         }
         int filesToFormat = parameters.files().size();
         if (parameters.stdin()) {

palantir-java-format/src/main/java/com/palantir/javaformat/java/UsageException.java

@@ -17,6 +17,7 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.Joiner;
+import javax.annotation.Nullable;
 
 /** Checked exception class for formatter command-line usage errors. */
 final class UsageException extends Exception {
@@ -88,7 +89,7 @@ final class UsageException extends Exception {
         super(buildMessage(checkNotNull(message)));
     }
 
-    private static String buildMessage(String message) {
+    private static String buildMessage(@Nullable String message) {
         StringBuilder builder = new StringBuilder();
         if (message != null) {
             builder.append(message).append('\n');

palantir-java-format/src/main/java/com/palantir/javaformat/java/javadoc/JavadocWriter.java

@@ -28,6 +28,7 @@
 
 import com.google.common.collect.ImmutableSet;
 import com.google.common.collect.Ordering;
+import javax.annotation.Nullable;
 
 /**
  * Stateful object that accepts "requests" and "writes," producing formatted Javadoc.
@@ -53,7 +54,10 @@ final class JavadocWriter {
     private int remainingOnLine;
     private boolean atStartOfLine;
     private RequestedWhitespace requestedWhitespace = NONE;
+
+    @Nullable
     private Token requestedMoeBeginStripComment;
+
     private int indentForMoeEndStripComment;
     private boolean wroteAnythingSignificant;