Java BeanUtils.populate方法代码示例

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * map to bean
 * 转换过程中，由于属性的类型不同，需要分别转换。
 * java 反射机制，转换过程中属性的类型默认都是 String 类型，否则会抛出异常，而 BeanUtils 项目，做了大量转换工作，比 java 反射机制好用
 * BeanUtils 的 populate 方法，对 Date 属性转换，支持不好，需要自己编写转换器
 *
 * @param map  待转换的 map
 * @param bean 满足 bean 格式，且需要有无参的构造方法; bean 属性的名字应该和 map 的 key 相同
 * @throws IllegalAccessException
 * @throws InvocationTargetException
 */
private static void mapToBean(Map<String, Object> map, Object bean) throws IllegalAccessException, InvocationTargetException {

    //注册几个转换器
    ConvertUtils.register(new SqlDateConverter(null), java.sql.Date.class);
    ConvertUtils.register(new SqlTimestampConverter(null), java.sql.Timestamp.class);
    //注册一个类型转换器  解决 common-beanutils 为 Date 类型赋值问题
    ConvertUtils.register(new Converter() {
        //  @Override
        public Object convert(Class type, Object value) { // type : 目前所遇到的数据类型。  value :目前参数的值。
            // System.out.println(String.format("value = %s", value));

            if (value == null || value.equals("") || value.equals("null"))
                return null;
            Date date = null;
            try {
                SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
                date = dateFormat.parse((String) value);
            } catch (Exception e) {

                e.printStackTrace();
            }

            return date;
        }

    }, Date.class);

    BeanUtils.populate(bean, map);
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
public void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException{
    User user = new User();
    HashMap map = new HashMap();
    Enumeration names = request.getParameterNames();
    while (names.hasMoreElements()) {
        String name = (String) names.nextElement();
        map.put(name, request.getParameterValues(name));
    }
    try{
        BeanUtils.populate(user, map); //BAD

        BeanUtilsBean beanUtl = BeanUtilsBean.getInstance();
        beanUtl.populate(user, map); //BAD
    }catch(Exception e){
        e.printStackTrace();
    }
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/********************************** get *************************************/

    @Override
    public <T> T _get(Class<T> clazz, Long pv) throws Exception {
        Map<String, Object> param = new HashMap<>();

        String tableName = GeneralMapperReflectUtil.getTableName(clazz);
        String primaryKey = GeneralMapperReflectUtil.getPrimaryKey(clazz);
        List<String> queryColumn = GeneralMapperReflectUtil.getAllColumns(clazz, false);

        param.put("_table_", tableName);
        param.put("_pk_", primaryKey);
        param.put("_pv_", pv);
        param.put("_query_column_", queryColumn);
        Map map = sqlSession.selectOne(Crudable.GET, param);
        T t = clazz.newInstance();
        BeanUtils.populate(t, map);
        return t;
    }
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
* 类实现 Maps --> Bean  
* @param objClass
* @param objMaps
*/
  public static  <T> List<T> map2BeanList(List<Map<String, Object>> objMaps, Class<T> objClass) {  
      if (objMaps == null || objClass == null) {  
          return Collections.emptyList();  
      }  
      List<T> objList = new ArrayList<T>();
      try { 
      	for(Map<String, Object> mapObj : objMaps) {
       	T obj = objClass.newInstance();
           BeanUtils.populate(obj, mapObj);
           objList.add(obj);
      	}
      } catch (Exception e) {  
      	logger.error(e.getMessage());
      } 
      return objList;
  }
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
@Test
public void testMap2Bean() throws Exception {
    Map<String, Object> map = Maps.newHashMap();
    map.put("Username", "jonnyliu");
    map.put("Age", 39);
    User user = new User();
    Map map1 = Maps.newHashMap();
    map.forEach((x, y) -> {
        char[] charArray = x.toCharArray();
        charArray[0] = Character.toLowerCase(charArray[0]);
        map1.put(new String(charArray), y);
    });
    BeanUtils.populate(user, map1);

    System.out.println(user);
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
public static <T> T mapToBean(Map<String, Object> map, Class<T> cls){
	
	T bean = null;
	
	try {
		bean = cls.newInstance();
		// 将map中的数据封装到javabean
		BeanUtils.populate(bean, map);
	} catch (Exception e) {
		e.printStackTrace();
	}
	
	return bean;
	
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
static void applyFrom(final String value, final Object object) {
  if (value == null) {
    return;
  }

  final Map<String, String> kv = Splitter.on(",").trimResults().omitEmptyStrings()
      .withKeyValueSeparator("=").split(value);

  try {
    BeanUtils.populate(object, kv);
  } catch (final IllegalAccessException | InvocationTargetException e) {
    throw new RuntimeException(e);
  }
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * 新建实例
 * 
 * @param cls
 *            实体类
 * @param list
 *            实体属性Map
 * @return
 */
public static final <E> E newInstance(Class<E> cls, Map<String, ?> map) {
    E object = null;
    try {
        object = cls.newInstance();
        BeanUtils.populate(object, map);
    } catch (Exception e) {
        throw new InstanceException(e);
    }
    return object;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
@Override
public <T> List<T> _gets(Class<T> clazz, CrudParam crudParam) throws Exception {
    Map<String, Object> param = new HashMap<>();
    String tableName = GeneralMapperReflectUtil.getTableName(clazz);

    param.put("_table_", tableName);
    param.put("_query_column_", null == crudParam.getQueryColumn() ? GeneralMapperReflectUtil.getAllColumns(clazz, false) : crudParam.getQueryColumn());
    Object entity = crudParam.getEntity();
    if (entity != null) {
        param.put("_condition_param_", null == crudParam.getConditionParam() ? GeneralMapperReflectUtil.getFieldValueMappingExceptNull(entity, false) : crudParam.getConditionParam());
    }

    param.put("_where_exp_", crudParam.getConditionExp());
    param.put("_order_exp_", crudParam.getOrderExp());
    param.put("_pks_", crudParam.getPks());
    //param.put("",);

    if (crudParam.getPageSize() != null && crudParam.getPageNo() != null) {
        Map<String, Integer> page = new HashMap<>();
        page.put("pageSize", crudParam.getPageSize());
        page.put("startRowNo", (crudParam.getPageNo() - 1) * crudParam.getPageSize());
        param.put("page", page);
    }

    List<Map> maps = sqlSession.selectList(Crudable.GETS, param);
    List<T> ts = new ArrayList<>();
    for (Map map : maps) {
        T t = clazz.newInstance();
        BeanUtils.populate(t, map);
        ts.add(t);
    }
    return ts;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * 新建实例
 * 
 * @param cls 实体类
 * @param list 实体属性Map
 * @return
 */
public static final <E> E newInstance(Class<E> cls, Map<String, ?> map) {
	E object = null;
	try {
		object = cls.newInstance();
		BeanUtils.populate(object, map);
	} catch (Exception e) {
		throw new InstanceException(e);
	}
	return object;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * 新建实例
 * 
 * @param cls
 *            实体类
 * @param list
 *            实体属性Map
 * @return
 */
public static final <E> E newInstance(Class<E> cls, Map<String, ?> map) {
	E object = null;
	try {
		object = cls.newInstance();
		BeanUtils.populate(object, map);
	} catch (Exception e) {
		throw new InstanceException(e);
	}
	return object;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
protected <T> T assembleRequestParamForBean(HttpServletRequest request, Class<T> clazz, Page<?> page) {
    Map<String, String> paraMap = assembleRequestParamForMap(request, page);
    T t = null;
    try {
        t = clazz.newInstance();
        BeanUtils.populate(t, paraMap);
    } catch (Exception e) {
        throw new RuntimeException("MAP转换BEAN时出错。");
    }
    return t;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * 将Bean的属性值修改为Map中对应的值
 *
 * @param property 一个Map对象，封装了相应的Bean类中的属性
 * @param bean     需要修改的Bean类
 * @return 返回一个属性已修改的Bean类实例
 */
public static <T extends Object> T modifyBean(Map<String, ? extends Object> property, T bean) {
    try {
        BeanUtils.populate(bean, property);
        return bean;
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
 * 将一个Map对象转换成一个Bean对象
 *
 * @param property 一个Map对象，封装了相应的Bean中的属性
 * @param clazz    需要转换成的Bean
 * @return 返回一个封装好的Bean类实例，封装失败返回null
 */
public static <T extends Object> T toBean(Map<String, ? extends Object> property, Class<T> clazz) {
    T bean = null;
    try {
        bean = clazz.newInstance();
        BeanUtils.populate(bean, property);
    } catch (Exception e) {
        throw new RuntimeException(e);
    }
    return bean;
}
 

import org.apache.commons.beanutils.BeanUtils; //导入方法依赖的package包/类
/**
* 类实现 Map --> Bean  
* @param map
* @param clazz
*/
  public static <T> T map2Bean(Map<String, Object> map, Class<T> clazz) {  
      if (map == null || clazz == null) {  
          return null;  
      }  
      try {  
      	T obj = clazz.newInstance();
          BeanUtils.populate(obj, map);
          return obj;
      } catch (Exception e) {  
      	logger.error(e.getMessage());
      }
      return null;
  }