esayexcel+Javaassist动态生成表对象

            org.javassist
            javassist
            3.28.0-GA
        

public class Test {
	public static final Map NEW_FIELD_MAP = new HashMap<>();
	
	public static String toUpperCase4Index(String string) {
        char[] methodName = string.toCharArray();
        methodName[0] = toUpperCase(methodName[0]);
        return String.valueOf(methodName);
    }
    public static Object test1() throws Exception {

        ClassPool pool = ClassPool.getDefault();
        //新建一个类
        CtClass ctClass = pool.makeClass("com.example.bugcount.MyDailyReport");
        CtConstructor cons = new CtConstructor(new CtClass[] {}, ctClass);
        cons.setBody("{}");
        //添加构造方法
        ctClass.addConstructor(cons);
        //创建字段
        for(String fieldName: NEW_FIELD_MAP.keySet()) {
            // 字段类型
            String fieldType = NEW_FIELD_MAP.get(fieldName).getClass().getName();
            // 创建新字段
            CtField ctField = new CtField(pool.get(fieldType), fieldName, ctClass);
            ctField.setModifiers(Modifier.PRIVATE);
            ctClass.addField(ctField);

            List attributeInfos = ctField.getFieldInfo().getAttributes();
            AnnotationsAttribute annotationsAttribute = !attributeInfos.isEmpty()?(AnnotationsAttribute) attributeInfos.get(0):
                    new AnnotationsAttribute(ctField.getFieldInfo().getConstPool(), AnnotationsAttribute.visibleTag);
            ConstPool fieldConstPool = ctField.getFieldInfo().getConstPool();
            if(!"".equals(NEW_FIELD_MAP.get(fieldName))){
                Annotation annotation = new Annotation("com.alibaba.excel.annotation.ExcelProperty", fieldConstPool);
                StringMemberValue[] elements = {new StringMemberValue((String)NEW_FIELD_MAP.get(fieldName), fieldConstPool)};
                ArrayMemberValue amv = new ArrayMemberValue(ctField.getFieldInfo().getConstPool());
                amv.setValue(elements);
                //添加注解的值
                annotation.addMemberValue("value", amv);
                annotationsAttribute.addAnnotation(annotation);
            }else {
                Annotation annotation = new Annotation("com.alibaba.excel.annotation.ExcelIgnore", fieldConstPool);
                annotationsAttribute.addAnnotation(annotation);
            }
            ctField.getFieldInfo().addAttribute(annotationsAttribute);
			//添加set get方法
            ctClass.addMethod(CtNewMethod.setter( "set" + toUpperCase4Index(fieldName),ctField));
            ctClass.addMethod(CtNewMethod.getter( "get" + toUpperCase4Index(fieldName),ctField));
        }
        //返回对象
        return ctClass.toClass().newInstance();
    }
    public static void main(String[] args) throws Exception {
        NEW_FIELD_MAP.put("test1","测试1");
        NEW_FIELD_MAP.put("test2","");
        NEW_FIELD_MAP.put("test3","测试3");
        test1();
    }
}