Merge pull request #790 from muyuanjin/#789

fix #789 NPE in JsonBuildHelper

Author: shalousun

src/main/java/com/ly/doc/utils/JavaClassUtil.java

@@ -835,13 +835,15 @@ private static String getFieldGenericType(JavaField javaField, ClassLoader class
 
     private static String getReturnGenericType(JavaMethod javaMethod, ClassLoader classLoader) {
         String methodName = javaMethod.getName();
-        String canonicalClassName = javaMethod.getDeclaringClass().getCanonicalName();
+        // `BinaryName` is the correct name for inner classes required by `ClassLoader.loadClass`
+        // and `Class.forName`, as inner class paths use `$` instead of `.`.
+        String binaryName = javaMethod.getDeclaringClass().getBinaryName();
         try {
             Class<?> c;
             if (Objects.nonNull(classLoader)) {
-                c = classLoader.loadClass(canonicalClassName);
+                c = classLoader.loadClass(binaryName);
             } else {
-                c = Class.forName(canonicalClassName);
+                c = Class.forName(binaryName);
             }
 
             Method m = c.getDeclaredMethod(methodName);

src/test/java/com/ly/doc/helper/JsonBuildHelperTest.java

@@ -0,0 +1,59 @@
+package com.ly.doc.helper;
+
+import com.ly.doc.builder.ProjectDocConfigBuilder;
+import com.ly.doc.model.ApiConfig;
+import com.thoughtworks.qdox.JavaProjectBuilder;
+import com.thoughtworks.qdox.model.JavaClass;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.util.HashMap;
+import java.util.HashSet;
+
+/**
+ * @author muyuanjin
+ * @date 2024/5/16 下午7:15
+ */
+class JsonBuildHelperTest {
+    /**
+     * com.ly.doc.helper.JsonBuildHelper#buildJson
+     * issue:NPE in JsonBuildHelper #789
+     */
+    @Test
+    void testBuildJsonWithNPE() {
+        ApiConfig apiConfig = new ApiConfig();
+        JavaProjectBuilder projectBuilder = JavaProjectBuilderHelper.create();
+        Assertions.assertNotNull(projectBuilder.getClassByName(getClass().getName()));
+        JavaClass taskType = projectBuilder.getClassByName(Task.class.getName());
+        Assertions.assertNotNull(taskType);
+        Assertions.assertFalse(taskType.getMethods().isEmpty());
+        ProjectDocConfigBuilder builder = new ProjectDocConfigBuilder(apiConfig, projectBuilder);
+        Assertions.assertNull(builder.getClassByName(getClass().getName()));
+        Assertions.assertNotNull(builder.getClassByName(Task.class.getName()));
+        Assertions.assertFalse(builder.getClassByName(Task.class.getName()).getMethods().isEmpty());
+        String json = JsonBuildHelper.buildJson(Task.class.getName(),
+                Task.class.getCanonicalName(),
+                false, 0, new HashMap<>(16), new HashSet<>(), builder
+        );
+        System.out.println(json);
+    }
+
+    interface Serialize<T extends Serialize<T>> {
+        @SuppressWarnings("unchecked")
+        default Class<T> getOriginalClass() {
+            return (Class<T>) this.getClass();
+        }
+    }
+
+    public static class Task implements Serialize<Task> {
+        private String taskType;
+
+        public String getTaskType() {
+            return taskType;
+        }
+
+        public void setTaskType(String taskType) {
+            this.taskType = taskType;
+        }
+    }
+}