java根据对象属性值过滤集合数据

痛定思痛。 2022-06-01 00:41 348阅读 0赞

package com.zr.List;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import org.apache.commons.collections.CollectionUtils;
    import org.apache.commons.collections.Predicate;
    import org.apache.commons.collections.PredicateUtils;
    
    /**
     * 根据对象属性值过滤集合数据 
     */
    public class FilterList {
    
    	public static void main(String[] args) {
    		
    		List<User> userList = new ArrayList<User>();
    
    		userList.add(new User("李小龙", "男", 74));
    		userList.add(new User("李连杰", "男", 54));
    		userList.add(new User("刘亦菲", "女", 29));
    		userList.add(new User("杨紫琼", "女", 51));
    
    		// 过滤多个属性值
    		Predicate filter1 = new MyPredicate("username", "李连杰");
    		Predicate filter2 = new MyPredicate("age", 54);
    		Predicate filter3 = new MyPredicate("gender", "男");
    
    		Predicate any1 = PredicateUtils.andPredicate(filter1, filter2);
    		Predicate any2 = PredicateUtils.andPredicate(any1, filter3);
    
    		@SuppressWarnings("unchecked")
    		List<User> list = (List<User>) CollectionUtils.select(userList, any2);
    		System.out.println("筛选属性后结果集:\n" + list);
    
    		@SuppressWarnings("unchecked")
    		List<User> rejectList = (List<User>) CollectionUtils.selectRejected(
    				userList, filter3);
    		System.out.println("筛选属性后结果集补集:\n" + rejectList);
    		
    
    	}
    
    }

package com.zr.List;
    
    import java.math.BigDecimal;
    
    import org.apache.commons.beanutils.PropertyUtils;
    import org.apache.commons.collections.Predicate;
    
    public class MyPredicate implements Predicate {
    
    	private String property;
    
    	private Object value;
    
    	public MyPredicate(String property, Object value) {
    		this.property = property;
    		this.value = value;
    	}
    
    	public boolean evaluate(Object object) {
    		// TODO Auto-generated method stub
    		try {
    			Object beanValue;
    			if (property.indexOf(".") > 0) {
    				beanValue = PropertyUtils.getNestedProperty(object, property);
    			} else {
    				beanValue = PropertyUtils.getProperty(object, property);
    			}
    			if (beanValue == null) {
    				return false;
    			}
    			if (!value.getClass().equals(beanValue.getClass())) {
    				throw new RuntimeException("value.class!=beanValue.class");
    			}
    			return myCompare(beanValue, value);
    
    		} catch (Exception e) {
    			throw new RuntimeException(e.getMessage(), e.getCause());
    		}
    	}
    
    	private boolean myCompare(Object value, Object beanValue) {
    		if (beanValue.getClass().equals(Integer.class)) {
    			if (((Integer) beanValue).equals(value)) {
    				return true;
    			}
    		}
    		if (beanValue.getClass().equals(BigDecimal.class)) {
    			if (((BigDecimal) beanValue).compareTo((BigDecimal) value) == 0) {
    				return true;
    			}
    		}
    		if (beanValue.getClass().equals(String.class)) {
    			if (beanValue.toString().equals(value.toString())) {
    				return true;
    			}
    		}
    		return false;
    	}
    
    }

<dependency>
    			<groupId>commons-collections</groupId>
    			<artifactId>commons-collections</artifactId>
    			<version>3.2.2</version>
    		</dependency>