Perform additional validation & fail earlier for incorrect arguments

javapoet/src/main/java/com/palantir/javapoet/AnnotationSpec.java

@@ -127,6 +127,7 @@ public static AnnotationSpec get(Annotation annotation) {
     }
 
     public static AnnotationSpec get(Annotation annotation, boolean includeDefaultValues) {
+        checkNotNull(annotation, "annotation == null");
         Builder builder = builder(annotation.annotationType());
         try {
             Method[] methods = annotation.annotationType().getDeclaredMethods();
@@ -157,6 +158,7 @@ public static AnnotationSpec get(Annotation annotation, boolean includeDefaultVa
     }
 
     public static AnnotationSpec get(AnnotationMirror annotation) {
+        checkNotNull(annotation, "annotation == null");
         TypeElement element = (TypeElement) annotation.getAnnotationType().asElement();
         AnnotationSpec.Builder builder = AnnotationSpec.builder(ClassName.get(element));
         Visitor visitor = new Visitor(builder);
@@ -230,6 +232,8 @@ public Builder addMember(String name, String format, Object... args) {
         }
 
         public Builder addMember(String name, CodeBlock codeBlock) {
+            checkNotNull(name, "name == null");
+            checkNotNull(codeBlock, "codeBlock == null");
             List<CodeBlock> values = members.computeIfAbsent(name, _k -> new ArrayList<>());
             values.add(codeBlock);
             return this;

javapoet/src/main/java/com/palantir/javapoet/ArrayTypeName.java

@@ -36,7 +36,7 @@ private ArrayTypeName(TypeName componentType) {
 
     private ArrayTypeName(TypeName componentType, List<AnnotationSpec> annotations) {
         super(annotations);
-        this.componentType = checkNotNull(componentType, "rawType == null");
+        this.componentType = checkNotNull(componentType, "componentType == null");
     }
 
     public TypeName componentType() {
@@ -100,6 +100,7 @@ public static ArrayTypeName get(ArrayType mirror) {
     }
 
     static ArrayTypeName get(ArrayType mirror, Map<TypeParameterElement, TypeVariableName> typeVariables) {
+        checkNotNull(mirror, "mirror == null");
         return new ArrayTypeName(get(mirror.getComponentType(), typeVariables));
     }
 
@@ -109,6 +110,6 @@ public static ArrayTypeName get(GenericArrayType type) {
     }
 
     static ArrayTypeName get(GenericArrayType type, Map<Type, TypeVariableName> map) {
-        return ArrayTypeName.of(get(type.getGenericComponentType(), map));
+        return of(get(type.getGenericComponentType(), map));
     }
 }

javapoet/src/main/java/com/palantir/javapoet/ClassName.java

@@ -17,13 +17,13 @@
 
 import static com.palantir.javapoet.Util.checkArgument;
 import static com.palantir.javapoet.Util.checkNotNull;
+import static com.palantir.javapoet.Util.checkState;
 
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
 import javax.lang.model.element.Element;
 import javax.lang.model.element.PackageElement;
 import javax.lang.model.element.TypeElement;
@@ -68,9 +68,11 @@ private ClassName(String packageName, ClassName enclosingClassName, String simpl
     private ClassName(
             String packageName, ClassName enclosingClassName, String simpleName, List<AnnotationSpec> annotations) {
         super(annotations);
-        this.packageName = Objects.requireNonNull(packageName, "packageName == null");
+        this.packageName = checkNotNull(packageName, "packageName == null");
+        checkState(enclosingClassName == null || enclosingClassName.packageName.equals(packageName),
+                "enclosing class is in wrong package");
         this.enclosingClassName = enclosingClassName;
-        this.simpleName = simpleName;
+        this.simpleName = checkNotNull(simpleName, "simpleName == null");
         this.canonicalName = enclosingClassName != null
                 ? (enclosingClassName.canonicalName + '.' + simpleName)
                 : (packageName.isEmpty() ? simpleName : packageName + '.' + simpleName);
@@ -168,7 +170,7 @@ public String simpleName() {
     /**
      * Returns the full class name of this class.
      * Like {@code "java.util.Map.Entry"} for {@link Map.Entry}.
-     * */
+     */
     public String canonicalName() {
         return canonicalName;
     }
@@ -250,6 +252,7 @@ public ClassName defaultAction(Element _enclosingElement, Void _p) {
      * instances without such restrictions.
      */
     public static ClassName bestGuess(String classNameString) {
+        checkNotNull(classNameString, "classNameString == null");
         // Add the package name, like "java.util.concurrent", or "" for no package.
         int p = 0;
         while (p < classNameString.length() && Character.isLowerCase(classNameString.codePointAt(p))) {

javapoet/src/main/java/com/palantir/javapoet/CodeBlock.java

@@ -16,6 +16,7 @@
 package com.palantir.javapoet;
 
 import static com.palantir.javapoet.Util.checkArgument;
+import static com.palantir.javapoet.Util.checkNotNull;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
@@ -129,6 +130,8 @@ public static CodeBlock of(String format, Object... args) {
      * would produce {@code String s, Object o, int i}.
      */
     public static CodeBlock join(Iterable<CodeBlock> codeBlocks, String separator) {
+        checkNotNull(codeBlocks, "codeBlocks == null");
+        checkNotNull(separator, "separator == null");
         return StreamSupport.stream(codeBlocks.spliterator(), false).collect(joining(separator));
     }
 
@@ -138,6 +141,7 @@ public static CodeBlock join(Iterable<CodeBlock> codeBlocks, String separator) {
      * {@code int i} using {@code ", "} would produce {@code String s, Object o, int i}.
      */
     public static Collector<CodeBlock, ?, CodeBlock> joining(String separator) {
+        checkNotNull(separator, "separator == null");
         return Collector.of(
                 () -> new CodeBlockJoiner(separator, builder()),
                 CodeBlockJoiner::add,
@@ -151,6 +155,9 @@ public static CodeBlock join(Iterable<CodeBlock> codeBlocks, String separator) {
      * {@code int i} using {@code ", "} would produce {@code String s, Object o, int i}.
      */
     public static Collector<CodeBlock, ?, CodeBlock> joining(String separator, String prefix, String suffix) {
+        checkNotNull(separator, "separator == null");
+        checkNotNull(prefix, "prefix == null");
+        checkNotNull(suffix, "suffix == null");
         Builder builder = builder().add("$N", prefix);
         return Collector.of(
                 () -> new CodeBlockJoiner(separator, builder), CodeBlockJoiner::add, CodeBlockJoiner::merge, joiner -> {
@@ -192,6 +199,8 @@ public boolean isEmpty() {
          * value {@code java.lang.Integer.class} in the argument map.
          */
         public Builder addNamed(String format, Map<String, ?> arguments) {
+            checkNotNull(format, "format == null");
+            checkNotNull(arguments, "arguments == null");
             int p = 0;
 
             for (String argument : arguments.keySet()) {
@@ -243,6 +252,7 @@ public Builder addNamed(String format, Map<String, ?> arguments) {
         }
 
         public Builder add(CodeBlock codeBlock) {
+            checkNotNull(codeBlock, "codeBlock == null");
             formatParts.addAll(codeBlock.formatParts);
             args.addAll(codeBlock.args);
             return this;
@@ -260,6 +270,8 @@ public Builder add(CodeBlock codeBlock) {
          * error.
          */
         public Builder add(String format, Object... args) {
+            checkNotNull(format, "format == null");
+            checkNotNull(args, "args == null");
             boolean hasRelative = false;
             boolean hasIndexed = false;
 
@@ -421,6 +433,7 @@ private TypeName argToType(Object o) {
          * Shouldn't contain braces or newline characters.
          */
         public Builder beginControlFlow(String controlFlow, Object... args) {
+            checkNotNull(controlFlow, "controlFlow == null"); // otherwise string concat turns this into non-null
             add(controlFlow + " {\n", args);
             indent();
             return this;
@@ -431,6 +444,7 @@ public Builder beginControlFlow(String controlFlow, Object... args) {
          *     Shouldn't contain braces or newline characters.
          */
         public Builder nextControlFlow(String controlFlow, Object... args) {
+            checkNotNull(controlFlow, "controlFlow == null"); // otherwise string concat turns this into non-null
             unindent();
             add("} " + controlFlow + " {\n", args);
             indent();
@@ -448,6 +462,7 @@ public Builder endControlFlow() {
          *     "while(foo == 20)". Only used for "do/while" control flows.
          */
         public Builder endControlFlow(String controlFlow, Object... args) {
+            checkNotNull(controlFlow, "controlFlow == null"); // otherwise string concat turns this into non-null
             unindent();
             add("} " + controlFlow + ";\n", args);
             return this;
@@ -461,6 +476,7 @@ public Builder addStatement(String format, Object... args) {
         }
 
         public Builder addStatement(CodeBlock codeBlock) {
+            checkNotNull(codeBlock, "codeBlock == null");
             return addStatement("$L", codeBlock);
         }
 

javapoet/src/main/java/com/palantir/javapoet/CodeWriter.java

@@ -16,6 +16,7 @@
 package com.palantir.javapoet;
 
 import static com.palantir.javapoet.Util.checkArgument;
+import static com.palantir.javapoet.Util.checkNoNullElement;
 import static com.palantir.javapoet.Util.checkNotNull;
 import static com.palantir.javapoet.Util.checkState;
 import static com.palantir.javapoet.Util.stringLiteralWithDoubleQuotes;
@@ -133,6 +134,7 @@ public CodeWriter popPackage() {
     }
 
     public CodeWriter pushType(TypeSpec type) {
+        checkNotNull(type, "type == null");
         this.typeSpecStack.add(type);
         return this;
     }
@@ -143,6 +145,7 @@ public CodeWriter popType() {
     }
 
     public void emitComment(CodeBlock codeBlock) throws IOException {
+        checkNotNull(codeBlock, "codeBlock == null");
         trailingNewline = true; // Force the '//' prefix for the comment.
         comment = true;
         try {
@@ -154,6 +157,7 @@ public void emitComment(CodeBlock codeBlock) throws IOException {
     }
 
     public void emitJavadoc(CodeBlock javadocCodeBlock) throws IOException {
+        checkNotNull(javadocCodeBlock, "javadocCodeBlock == null");
         if (javadocCodeBlock.isEmpty()) {
             return;
         }
@@ -169,6 +173,7 @@ public void emitJavadoc(CodeBlock javadocCodeBlock) throws IOException {
     }
 
     public void emitAnnotations(List<AnnotationSpec> annotations, boolean inline) throws IOException {
+        checkNoNullElement(annotations, "annotations");
         for (AnnotationSpec annotationSpec : annotations) {
             annotationSpec.emit(this, inline);
             emit(inline ? " " : "\n");
@@ -180,6 +185,8 @@ public void emitAnnotations(List<AnnotationSpec> annotations, boolean inline) th
      * be emitted.
      */
     public void emitModifiers(Set<Modifier> modifiers, Set<Modifier> implicitModifiers) throws IOException {
+        checkNoNullElement(modifiers, "modifiers");
+        checkNoNullElement(implicitModifiers, "implicitModifiers");
         if (modifiers.isEmpty()) {
             return;
         }
@@ -201,6 +208,7 @@ public void emitModifiers(Set<Modifier> modifiers) throws IOException {
      * everywhere else bounds are omitted.
      */
     public void emitTypeVariables(List<TypeVariableName> typeVariables) throws IOException {
+        checkNoNullElement(typeVariables, "typeVariables");
         if (typeVariables.isEmpty()) {
             return;
         }
@@ -258,6 +266,7 @@ public void emitJavadocWithParameters(CodeBlock javadoc, Iterable<ParameterSpec>
     }
 
     public void popTypeVariables(List<TypeVariableName> typeVariables) {
+        checkNoNullElement(typeVariables, "typeVariables");
         typeVariables.forEach(typeVariable -> currentTypeVariables.remove(typeVariable.name()));
     }
 
@@ -274,6 +283,7 @@ public CodeWriter emit(CodeBlock codeBlock) throws IOException {
     }
 
     public CodeWriter emit(CodeBlock codeBlock, boolean ensureTrailingNewline) throws IOException {
+        checkNotNull(codeBlock, "codeBlock == null");
         int a = 0;
         ClassName deferredTypeName = null; // used by "import static" logic
         ListIterator<String> partIterator = codeBlock.formatParts().listIterator();
@@ -518,6 +528,7 @@ private ClassName stackClassName(int stackDepth, String simpleName) {
      * unnecessary trailing whitespace.
      */
     CodeWriter emitAndIndent(String s) throws IOException {
+        checkNotNull(s, "s == null");
         boolean first = true;
         for (String line : LINE_BREAKING_PATTERN.split(s, -1)) {
             // Emit a newline character. Make sure blank lines in Javadoc & comments look good.

javapoet/src/main/java/com/palantir/javapoet/FieldSpec.java

@@ -18,6 +18,7 @@
 import static com.palantir.javapoet.Util.checkArgument;
 import static com.palantir.javapoet.Util.checkNotNull;
 import static com.palantir.javapoet.Util.checkState;
+import static com.palantir.javapoet.Util.nonNullList;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
@@ -116,6 +117,7 @@ public String toString() {
 
     public static Builder builder(TypeName type, String name, Modifier... modifiers) {
         checkNotNull(type, "type == null");
+        checkNotNull(name, "name == null");
         checkArgument(SourceVersion.isName(name), "not a valid name: %s", name);
         return new Builder(type, name).addModifiers(modifiers);
     }
@@ -159,29 +161,37 @@ public Builder addJavadoc(CodeBlock block) {
         }
 
         public Builder addAnnotations(Iterable<AnnotationSpec> annotationSpecs) {
-            checkArgument(annotationSpecs != null, "annotationSpecs == null");
+            checkNotNull(annotationSpecs, "annotationSpecs == null");
             for (AnnotationSpec annotationSpec : annotationSpecs) {
-                this.annotations.add(annotationSpec);
+                addAnnotation(annotationSpec);
             }
             return this;
         }
 
         public Builder addAnnotation(AnnotationSpec annotationSpec) {
+            checkNotNull(annotationSpec, "annotationSpec == null");
             this.annotations.add(annotationSpec);
             return this;
         }
 
         public Builder addAnnotation(ClassName annotation) {
-            this.annotations.add(AnnotationSpec.builder(annotation).build());
-            return this;
+            return addAnnotation(AnnotationSpec.builder(annotation).build());
         }
 
         public Builder addAnnotation(Class<?> annotation) {
             return addAnnotation(ClassName.get(annotation));
         }
 
         public Builder addModifiers(Modifier... modifiers) {
-            Collections.addAll(this.modifiers, modifiers);
+            return addModifiers(nonNullList(modifiers, "modifiers"));
+        }
+
+        public Builder addModifiers(Iterable<Modifier> modifiers) {
+            checkNotNull(modifiers, "modifiers == null");
+            for (Modifier modifier : modifiers) {
+                checkNotNull(modifier, "modifiers contain null");
+                this.modifiers.add(modifier);
+            }
             return this;
         }
 

javapoet/src/main/java/com/palantir/javapoet/JavaFile.java

@@ -16,6 +16,7 @@
 package com.palantir.javapoet;
 
 import static com.palantir.javapoet.Util.checkArgument;
+import static com.palantir.javapoet.Util.checkNoNullElement;
 import static com.palantir.javapoet.Util.checkNotNull;
 
 import java.io.ByteArrayInputStream;
@@ -30,7 +31,6 @@
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.Arrays;
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.List;
@@ -99,6 +99,7 @@ private void fillAlwaysQualifiedNames(TypeSpec spec, Set<String> alwaysQualified
     }
 
     public void writeTo(Appendable out) throws IOException {
+        checkNotNull(out, "out == null");
         // First pass: emit the entire class, just to collect the types we'll need to import.
         CodeWriter importsCollector = new CodeWriter(NULL_APPENDABLE, indent, staticImports, alwaysQualify);
         emit(importsCollector);
@@ -129,6 +130,7 @@ public void writeTo(Path directory, Charset charset) throws IOException {
 
     /** Writes this to {@code filer}. */
     public void writeTo(Filer filer) throws IOException {
+        checkNotNull(filer, "filer == null");
         String fileName = packageName.isEmpty() ? typeSpec.name() : packageName + "." + typeSpec.name();
         List<Element> originatingElements = typeSpec.originatingElements();
         JavaFileObject filerSourceFile = filer.createSourceFile(fileName, originatingElements.toArray(new Element[0]));
@@ -167,10 +169,12 @@ public Path writeToPath(Path directory) throws IOException {
      * Returns the {@link Path} instance to which source is actually written.
      */
     public Path writeToPath(Path directory, Charset charset) throws IOException {
+        checkNotNull(directory, "directory == null");
         checkArgument(
                 Files.notExists(directory) || Files.isDirectory(directory),
                 "path %s exists but is not a directory.",
                 directory);
+        checkNotNull(charset, "charset == null");
         Path outputDirectory = directory;
         if (!packageName.isEmpty()) {
             for (String packageComponent : packageName.split("\\.", -1)) {
@@ -323,11 +327,10 @@ public Builder addStaticImport(Class<?> clazz, String... names) {
         }
 
         public Builder addStaticImport(ClassName className, String... names) {
-            checkArgument(className != null, "className == null");
-            checkArgument(names != null, "names == null");
+            checkNotNull(className, "className == null");
+            checkNoNullElement(names, "names");
             checkArgument(names.length > 0, "names array is empty");
             for (String name : names) {
-                checkArgument(name != null, "null entry in names array: %s", Arrays.toString(names));
                 staticImports.add(className.canonicalName() + "." + name);
             }
             return this;
@@ -347,7 +350,7 @@ public Builder skipJavaLangImports(boolean skipJavaLangImports) {
         }
 
         public Builder indent(String indent) {
-            this.indent = indent;
+            this.indent = checkNotNull(indent, "indent == null");
             return this;
         }