fix: prevent potential null access when retrieving source paths

src/main/java/com/appland/appmap/output/v1/CodeObject.java

@@ -6,6 +6,7 @@
 
 import javassist.CtBehavior;
 import javassist.CtClass;
+import javassist.bytecode.ClassFile;
 
 import java.lang.reflect.Modifier;
 import java.util.ArrayDeque;
@@ -194,11 +195,24 @@ public CodeObject(CodeObject src) {
    * @return An estimated source file path
    */
   public static String getSourceFilePath(CtClass classType) {
-    String[] parts = {
-      "src", "main", "java",
-      classType.getPackageName().replace('.', '/'),
-      classType.getClassFile().getSourceFile()
-    };
+    final List<String> parts = new ArrayList(Arrays.asList("src", "main", "java"));
+    final String packageName = classType.getPackageName();
+
+    if (packageName != null) {
+      parts.add(packageName.replace('.', '/'));
+    }
+
+    final ClassFile classFile = classType.getClassFile();
+    if (classFile != null) {
+      String sourceFile = classFile.getSourceFile();
+      if (sourceFile != null) {
+        parts.add(sourceFile);
+      } else {
+        final String className = classType.getName().replaceAll("\\$.*", "");
+        parts.add(className + ".java");
+      }
+    }
+
     return String.join("/", parts);
   }
 
@@ -209,7 +223,13 @@ public static String getSourceFilePath(CtClass classType) {
    * @return The root CodeObject
    */
   public static CodeObject createTree(String packageName) {
-    String[] packageTokens = packageName.split("\\.");
+    final List<String> packageTokens = new ArrayList();
+    if (packageName != null) {
+      for (String token : packageName.split("\\.")) {
+        packageTokens.add(token);
+      }
+    }
+
     CodeObject rootObject = null;
     CodeObject previousObject = null;
 
@@ -241,15 +261,19 @@ public static CodeObject createTree(String packageName) {
    */
   public static CodeObject createTree(CtClass classType) {
     String packageName = classType.getPackageName();
+    CodeObject classObj = new CodeObject(classType);
     CodeObject rootObject = CodeObject.createTree(packageName);
-    CodeObject pkgLeafObject = rootObject.get(packageName);
-    if (pkgLeafObject == null) {
-      Logger.println("failed to get leaf pkg object for package " + packageName);
-      return null;
-    }
+    if (rootObject == null) {
+      rootObject = classObj;
+    } else {
+      CodeObject pkgLeafObject = rootObject.get(packageName);
+      if (pkgLeafObject == null) {
+        Logger.println("failed to get leaf pkg object for package " + packageName);
+        return null;
+      }
 
-    CodeObject classObj = new CodeObject(classType);
-    pkgLeafObject.addChild(classObj);
+      pkgLeafObject.addChild(classObj);
+    }
 
     return rootObject;
   }

src/test/java/com/appland/appmap/output/v1/CodeObjectTest.java

@@ -0,0 +1,68 @@
+package src.test.java.com.appland.appmap.output.v1;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+import com.appland.appmap.output.v1.CodeObject;
+import com.appland.appmap.output.v1.Event;
+import com.appland.appmap.test.util.ClassBuilder;
+
+import javassist.CtClass;
+
+import org.apache.commons.lang3.StringUtils;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.util.List;
+
+public class CodeObjectTest {
+
+  /**
+   * Validate the objects in a CodeObject tree match the given names and types
+   * @param obj The root object
+   * @param names The names of the objects, beginning with the root
+   * @param types The types of the objects, beginning with the root
+   */
+  private void validateCodeObjectTree(CodeObject obj, String[] names, String[] types) {
+    CodeObject currentObject = obj;
+    assertTrue(currentObject != null);
+
+    for (int i = 0; currentObject != null; ++i) {
+      assertEquals(currentObject.name, names[i]);
+      assertEquals(currentObject.type, types[i]);
+
+      List<CodeObject> children = currentObject.getChildren();
+      if (children != null && children.size() > 0) {
+        currentObject = children.get(0);
+      } else {
+        currentObject = null;
+      }
+    }
+  }
+
+  @Test
+  public void testGetSourceFilePath() {
+    CtClass testClass = new ClassBuilder("testGetSourceFilePath1").ctClass();
+    assertEquals(CodeObject.getSourceFilePath(testClass), "src/main/java/testGetSourceFilePath1.java");
+
+    testClass = new ClassBuilder("com.myorg.testGetSourceFilePath2").ctClass();
+    assertEquals(CodeObject.getSourceFilePath(testClass), "src/main/java/com/myorg/testGetSourceFilePath2.java");
+  }
+
+  @Test
+  public void testCreateTree() {
+    CtClass testClass = new ClassBuilder("testCreateTree").ctClass();
+    validateCodeObjectTree(
+      CodeObject.createTree(testClass),
+      new String[] { "testCreateTree" },
+      new String[] { "class" }
+    );
+
+    testClass = new ClassBuilder("com.myorg.testCreateTree").ctClass();
+    validateCodeObjectTree(
+      CodeObject.createTree(testClass),
+      new String[] { "com", "myorg", "testCreateTree" },
+      new String[] { "package", "package", "class" }
+    );
+  }
+}

src/test/java/com/appland/appmap/test/util/ClassBuilderTest.java

@@ -4,7 +4,10 @@
 import org.junit.Test;
 import org.junit.contrib.java.lang.system.SystemOutRule;
 
+import javassist.CtClass;
+
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.assertEquals;
 
 public class ClassBuilderTest {
   @Rule
@@ -17,4 +20,11 @@ public void testBuild() throws Exception {
 
     assertTrue(testClass.isInstance(obj));
   }
-} 
+
+  @Test
+  public void testAttributes() {
+    CtClass testClass = new ClassBuilder("com.example.TestAttributes").ctClass();
+    assertEquals(testClass.getPackageName(), "com.example");
+    assertEquals(testClass.getClassFile().getSourceFile(), "TestAttributes.java");
+  }
+}