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java 實例化泛型且賦值

alac sheet exception generic style array sta 實例化 ESS

實例化泛型

Class <T> clazz = (Class <T>) ((ParameterizedType) new 
 Entity().getClass().getGenericSuperclass()).getActualTypeArguments()[0];
        T dto = clazz.newInstance();

泛型方法

    /**
     * 
     * @param clazz
     * @param book
     * @param sheetIndex
     * @param <T>
     * 
@return * @throws IllegalAccessException * @throws InstantiationException */ public static <T> List<T> toEntity(Class<T> clazz,Workbook book, int sheetIndex) throws IllegalAccessException, InstantiationException { List<T> list = new ArrayList<>();
// Class <T> clazz = (Class <T>) ((ParameterizedType) entity.getClass().getGenericSuperclass()).getActualTypeArguments()[0]; T dto = clazz.newInstance(); T dto2 = clazz.newInstance(); Field[] fields = clazz.getDeclaredFields(); Map<String, Field> fieldMap = new
LinkedHashMap<>(); for (Field field : fields) { String mod = Modifier.toString(field.getModifiers()); System.out.println("mod = " + mod); // 跳過靜態屬性 if (mod.indexOf("static") != -1) { continue; } // 取得註解的設置的屬性值 Description setField = field.getAnnotation(Description.class); if (setField != null) { String fieldName = setField.key(); String fieldType = setField.value(); // 必須,不然賦值會出現異常 field.setAccessible(true); fieldMap.put(fieldType, field); System.out.println("註解的屬性 fieldName = " + fieldName); System.out.println("註解的屬性 fieldType = " + fieldType); } } int num = 0; for (String key : fieldMap.keySet()) { num++; fieldMap.get(key).set(dto, "dto1:" + key + num); fieldMap.get(key).set(dto2, "dto2:" + key + num); } list.add(dto); return list; }

java 實例化泛型且賦值