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java澶嶅埗
Class<?> clazz = (obj != null) ? obj.getClass() : TargetClass.class;

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java澶嶅埗
// 鑾峰彇鎵€鏈夊叕寮€鏂规硶锛堝寘鎷埗绫荤殑锛?/span>
Method[] methods = clazz.getMethods();

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Method method = clazz.getDeclaredMethod("formatDate", Context.class, long.class);

// 绐佺牬private灏佸嵃
method.setAccessible(true);

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// 鏅€氬唴閮ㄧ被
Class<?> innerClazz = OuterClass.InnerClass.class;

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Class<?> anonymousClazz = OuterClass$1.class;

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java澶嶅埗
Class<?>[] innerClasses = outerClazz.getDeclaredClasses();
Arrays.stream(innerClasses).forEach(c -> System.out.println(c.getSimpleName()));

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private static final Map methodCache = new ConcurrentHashMap<>();

Method cachedMethod = methodCache.computeIfAbsent(methodKey, 
    k -> clazz.getDeclaredMethod(methodName, paramTypes));

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java澶嶅埗
Field field = clazz.getDeclaredField("FINAL_VALUE");
field.setAccessible(true);

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Field modifiersField = Field.class.getDeclaredField("modifiers");
modifiersField.setAccessible(true);
modifiersField.setInt(field, field.getModifiers() & ~Modifier.FINAL);

field.set(null, newValue); // 鍗遍櫓鎿嶄綔锛佹厧鐢紒

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Method method = clazz.getDeclaredMethod("parseJson", String.class);
Type[] genericTypes = method.getGenericParameterTypes();

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