反射找到成员

package com.yd.wmsc.util;

import java.beans.BeanInfo;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.List;

public class ReflectTest {
    public static List<String> getPrefixList(Class Clazz, String prefix) {
        List<String> list = new ArrayList<String>();
        try {
            // 或得bean类
            BeanInfo beninfo = Introspector.getBeanInfo(Clazz);
            Field[] fields = Clazz.getDeclaredFields();
            for (Field field : fields) {
                System.out.println(field.getName());
            }

            System.out.println("======================================");
            // 获得所有的属性描述
            PropertyDescriptor[] propertydescriptors = beninfo.getPropertyDescriptors();
            for (PropertyDescriptor pd : propertydescriptors) {
                System.out.println(pd.getName());
                if (pd.getName().startsWith(prefix)) {
                    list.add(pd.getName());
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }

    public static void main(String[] args) {
        ReflectTest.getPrefixList(ContentWordBean.class, "TX_TYPE_");
    }
}

package com.yd.wmsc.util;

import java.util.List;


public class ContentWordBean {

    //题目类型
    private String itemType;
    //序号
    private String serial;
    //题目内容
    private String title;
    //答案
    private List<String> answerList;
    //标准答案
    private String lastAnswer;
    //答案解析
    private String analysis;
    //难度系数
    private String koc;
    //分数
    private String score;
    //章名称
    private String chapterName;
    //节名称
    private String sectionName;
    //知识点
    private String knowledge;
    //图片
        public String getKnowledge() {
        return knowledge;
    }
    /*public void setKnowledge(String knowledge) {
        this.knowledge = knowledge;
    }*/
    /*public String getItemType() {
        return itemType;
    }
    public void setItemType(String itemType) {
        this.itemType = itemType;
    }
    public String getSerial() {
        return serial;
    }
    public void setSerial(String serial) {
        this.serial = serial;
    }
    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }
    public List<String> getAnswerList() {
        return answerList;
    }
    public void setAnswerList(List<String> answerList) {
        this.answerList = answerList;
    }
    public String getLastAnswer() {
        return lastAnswer;
    }
    public void setLastAnswer(String lastAnswer) {
        this.lastAnswer = lastAnswer;
    }
    public String getAnalysis() {
        return analysis;
    }
    public void setAnalysis(String analysis) {
        this.analysis = analysis;
    }
    public String getKoc() {
        return koc;
    }
    public void setKoc(String koc) {
        this.koc = koc;
    }
    public String getScore() {
        return score;
    }
    public void setScore(String score) {
        this.score = score;
    }
    public String getChapterName() {
        return chapterName;
    }
    public void setChapterName(String chapterName) {
        this.chapterName = chapterName;
    }
    public String getSectionName() {
        return sectionName;
    }
    public void setSectionName(String sectionName) {
        this.sectionName = sectionName;
    }
    */
}

package com.yd.wmsc.util;

import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
import java.util.Properties;

public class TestReflect {
    public static void main(String[] args) throws NoSuchFieldException{
        ContentWordBean content = new ContentWordBean();
        //topicbean.setChapter_id("123");
        List<String> fields=new ArrayList<String>();
        //fields.add("topic_id");
        //fields.add("node_id");
        getInsertSql(ContentWordBean.class,fields,"e_topic","");
        getSql(ContentWordBean.class,fields);
    }
    private static void getSql(Class className,List<String> suffixs) {
        try {
            //或得bean类
            BeanInfo beninfo = Introspector.getBeanInfo(className);
            //获得所有的属性描述
            PropertyDescriptor [] propertydescriptors = beninfo.getPropertyDescriptors();
            for(PropertyDescriptor pd:propertydescriptors){
                //获得读写方法
                System.out.println(pd.getName());
                System.out.println(pd.getReadMethod().getName());//读
                System.out.println(pd.getWriteMethod().getName());//写
                
            }
        } catch (IntrospectionException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }    
    }
    /**通常需要将一个bean对象通过get方法插入到表中，本方法可以动态的生成sql语句
     * 将对象的sql语句生成
     * suffixs长度为空，则对所有的field进行插入
     * table为插入的表名
     * */
    public static String getInsertSql(Class className,List<String> suffixs,String table,String beanName) throws NoSuchFieldException{
        if("".equals(table)){
            System.out.println("表名为空");
            return null;                    
        }
        String sqlparam = "";
        String sql ="insert into "+table+"(sqlparam) values(";
        String bean = beanName;
        if("".equals(bean)){
            //获得类名并且将第一个字母转为小写
            bean = className.getSimpleName();;
            bean = bean.substring(0, 1).toLowerCase()+bean.substring(1);
        }
        //获得这个类的所有方法
        Method[] methods = className.getMethods();
        //是否取所有的fields
        if(suffixs.size() == 0){
            //获得私有属性
            Field[] fields = className.getDeclaredFields();
            for(Field field:fields){
                suffixs.add(field.getName());
            }
            
            //获得共有属性
            fields = className.getFields();
            for(Field field:fields){
                suffixs.add(field.getName());
            }
        }
        System.out.println(suffixs);
        for(String suffix:suffixs)
        {
            for(Method method:methods){
                //判断是否由get方法
                if(method.getName().toLowerCase().equals("get"+suffix)){
                    try {
                        //Field field = className.getDeclaredField(suffix);
                        if (method.getReturnType() == java.lang.String.class){
                            sqlparam += suffix+",";
                            sql +="'"+"+bean +"."+method.getName()+"()+"',";
                        }else
                        if (method.getReturnType() == int.class)
                        {
                            sqlparam += suffix+",";
                            sql +="'+"+bean +"."+method.getName()+"()+',";
                        }
                            
                    } catch (SecurityException e) {
                        e.printStackTrace();
                    }
                }
            }        
        }
        sql = sql.replace("(sqlparam)", "("+sqlparam.substring(0, sqlparam.length()-1)+")");
        sql = """+sql.substring(0, sql.length()-1)+");"";
        System.out.println(sql);
        return sql;
    }
}

Clazz.getDeclaredFields 找到本类所有的成员

Clazz.getFields 找到本类及父类公有的成员

Introspector.getBeanInfo(clazz);

beninfo.getPropertyDescriptors()找到本类及父类所有的成员，但成员必须至少有get或set方法，并多一个class成员

Introspector.getBeanInfo(clazz, clazz.getSuperclass()); 只找到本类所有的成员，但成员必须至少有get或set方法

import java.util.List;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.reflect.FieldUtils;
import org.springframework.http.HttpStatus;
import org.springframework.web.server.ResponseStatusException;

@Slf4j
public class FieldsValidator {

  private FieldsValidator() {}

  public static void validateFields(Object object, List<String> fieldNames) {

    fieldNames.stream()
        .filter(fieldName -> fieldIsNotNull(object, fieldName))
        .findAny()
        .orElseThrow(
            () ->
                new ResponseStatusException(HttpStatus.BAD_REQUEST, fieldNames + " are all null"));
  }

  public static boolean fieldIsNotNull(Object object, String fieldName) {
    try {
      Object o = FieldUtils.readField(object, fieldName, true);
      return o == null ? false : true;
    } catch (IllegalAccessException e) {
      log.error("IllegalAccessException occurred", e);
      return false;
    }
  }
}