使用 ArrayListValuedHashMap 用于 MultiValuedMap

Question

预先感谢您，非常感谢！

我正在尝试使用 apache commons MultiValuedMap 实现。但是，我似乎无法导入正确的包？？？

这是我的进口：

package com.ge.digital.fleet.dataservice.impl.db;

import java.util.Arrays;

import java.util.Map;

import java.util.ArrayList;

import java.util.Collection;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import java.util.Set;

import org.apache.commons.collections4.MultiValuedMap;

import org.apache.commons.collections4.MultiValuedMap.ArrayListValuedHashMap;

//import org.apache.commons.collections4.map.MultiValueMap;

import com.ge.digital.fleet.dataservice.RefDataServiceInvalidDataException;

import com.ge.digital.fleet.dataservice.RefDataServiceUnavailableException;

public class RefDatabase {

    private static final Logger log = LoggerFactory.getLogger(RefDatabase.class);

    private MultiValuedMap<String, String> associationsMap = new ArrayListValuedHashMap<>();

//      private Map<String,Collection<String>> map = associationsMap.asMap();

我的 POM.xml 具有公共依赖项

  <dependency>

    <groupId>org.apache.commons</groupId>

    <artifactId>commons-collections4</artifactId>

    <version>4.1</version>

  </dependency>

但它会引发编译错误

[ERROR] C:\Users\212555427\devel\workspaces\jbds\iprcsmartsignal\fleet-predix-new\fleet.mt1.dataserviceimpl\src\main\java\com\ge\digital\fleet\dataservice\impl\db\RefDatabase.java:[11,53] error: cannot find symbol

[ERROR]   symbol:   class ArrayListValuedHashMap

[ERROR]   location: interface MultiValuedMap

[ERROR] C:\Users\212555427\devel\workspaces\jbds\iprcsmartsignal\fleet-predix-new\fleet.mt1.dataserviceimpl\src\main\java\com\ge\digital\fleet\dataservice\impl\db\RefDatabase.java:[21,62] error: cannot find symbol

[ERROR]   symbol:   class ArrayListValuedHashMap

[ERROR]   location: class RefDatabase

我尝试了几种导入组合，但没有成功。谢谢你！！！

Answer 1

看来这个组合有效，我不确定这是否正确？import org.apache.commons.collections4.MultiValuedMap;//import org.apache.commons.collections4.MultiValuedMap.ArrayListValuedHashMap;//import org.apache.commons.collections4.map.MultiValueMap;import org.apache.commons.collections4.multimap.*;//import org.apache.commons.collections4.*;//import org.apache.commons.collections4.MultiValuedMap.*;//import org.apache.commons.collections4.map.*;