解决：java.lang.IllegalArgumentException: Can not set java.lang.Boolean field

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我是靠谱客的博主怡然镜子，最近开发中收集的这篇文章主要介绍解决：java.lang.IllegalArgumentException: Can not set java.lang.Boolean field，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

问题场景

使用反射为Boolean类型变量赋值时，调用 java.lang.reflect.Field#setBoolean 报错

public class SetBooleanDemo {

    public static void main(String[] args) throws IllegalAccessException {
        BooleanObj obj = new BooleanObj();
        Class<? extends BooleanObj> booleanClass = obj.getClass();
        for (Field declaredField : booleanClass.getDeclaredFields()) {
            declaredField.setAccessible(true);
            declaredField.setBoolean(obj,Boolean.TRUE);
        }

        System.out.println(obj);
    }

    @Data
    public static class BooleanObj{
        private boolean bool1;
        private Boolean bool2;
    }
}

Exception in thread "main" java.lang.IllegalArgumentException: Can not set java.lang.Boolean field com.example.demo.reflect.SetBooleanDemo$BooleanObj.bool2 to (boolean)true
	at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:167)
	at sun.reflect.UnsafeFieldAccessorImpl.throwSetIllegalArgumentException(UnsafeFieldAccessorImpl.java:175)
	at sun.reflect.UnsafeObjectFieldAccessorImpl.setBoolean(UnsafeObjectFieldAccessorImpl.java:90)
	at java.lang.reflect.Field.setBoolean(Field.java:801)
	at com.example.demo.reflect.SetBooleanDemo.main(SetBooleanDemo.java:20)

无论切换成 declaredField.setBoolean(obj,Boolean.TRUE) 还是 declaredField.setBoolean(obj,Boolean.TRUE.booleanValue()) 都未能解决

本来是个小问题，但是搜了下博客都是答非所问

解决方式

使用 java.lang.reflect.Field#set即可

public class SetBooleanDemo {

    public static void main(String[] args) throws IllegalAccessException {
        BooleanObj obj = new BooleanObj();
        Class<? extends BooleanObj> booleanClass = obj.getClass();
        for (Field declaredField : booleanClass.getDeclaredFields()) {
            declaredField.setAccessible(true);
            declaredField.set(obj,Boolean.TRUE);
        }

        System.out.println(obj);
    }

    @Data
    public static class BooleanObj{
        private boolean bool1;
        private Boolean bool2;
    }
}