Java HashMap containsKey未返回true

我试图在hashmap中比较数据的键，以检查数据是否存在。但是，即使该密钥确实存在于数组中，containsKey仍将返回false。我用的是：

package timeTraveler.core;

import java.util.Arrays;

public class StringArrayHolder
{
    private final String[] data;
    //I do not want any client could change the array reference
    //this also explains why this field doesn't have a setter
    public StringArrayHolder(String[] data) 
    {
        this.data = data;
    }
    public String[] getData() 
    {
        return this.data;
    }
    @Override
    public int hashCode()
    {
        return Arrays.hashCode(data);
    }
    @Override
    public boolean equals(Object o)
    {
        if (o == null) 
        {
            System.out.println("NULL");
            return false;
        }
        if (o == this)
        {
            System.out.println("THIS");
            return true;
        }

        if (o instanceof StringArrayHolder) 
        {
            StringArrayHolder other = (StringArrayHolder)o;
            return Arrays.equals(this.data, other.data);
        }
        return false;
    }
    //just to print in console for testing purposes
    @Override
    public String toString() 
    {
        return Arrays.deepToString(data);
    }
}

我的比较是：

package timeTraveler.mechanics;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import timeTraveler.core.StringArrayHolder;

public class PathingData 
{
    /**
     * Entity data array
     */
    public Map<StringArrayHolder, List<int[]>> allEntityData;

    public PathingData()
    {
        allEntityData = new HashMap<StringArrayHolder, List<int[]>>();
    }
    /**
     * Adds an entity identifier (NBT)and MobType to the entity data ArrayList.  If the entity already exists inside of the ArrayList, then it skips it.
     * @param uuid
     */
    public void addEntity(StringArrayHolder entityData)
    {       
        System.out.println(entityData);
        if(!allEntityData.containsKey(entityData))
        {
            System.out.println("Adding entity!");
            allEntityData.put(entityData, new ArrayList<int[]>());
        }
        else
        {
            System.out.println("ENTITY ALREADY EXISTS IN ARRAY");
        }
    }
    /**
     * Adds data (X, Y, and Z) to the corresponding identifier (NBT) for the entity.  If the entity's identifier does not exist, then it prints out a line that says the identifier cannot be found.
     * @param uuid
     * @param data
     */
    public void addData(StringArrayHolder entityData, String data)
    {
        System.out.println(entityData);
        if(allEntityData.containsKey(entityData))
        {
            System.out.println("Adding data to entity!");
            int[] rawData = new int[3];
            String[] pureData = data.split(",");

            rawData[0] = Integer.parseInt(pureData[0]);
            rawData[1] = Integer.parseInt(pureData[1]);
            rawData[2] = Integer.parseInt(pureData[2]);

            List<int[]> entityLocData = allEntityData.get(entityData);
            entityLocData.add(rawData);
            allEntityData.put(entityData, entityLocData);
        }
        else
        {
            System.out.println("ENTITY DOES NOT EXIST IN ARRAY! :(");
        }
    }
    /**
     * Gets the data for a specific UUID (Unique ID) for an entity.
     * @param uuid
     * @return
     */
    public List<int[]> getDataForIdentifier(StringArrayHolder entityData)
    {
        List<int[]> entityLoc = allEntityData.get(entityData);
        return entityLoc;
    }
    /**
     * Clears all entities and their corresponding data from the map.
     */
    public void clearAllEntitiesAndData()
    {
        allEntityData.clear();
    }

    /**
     * Checks if entity exists inside of array
     * @param entityData
     * @return
     */
    public boolean doesEntityExist(StringArrayHolder entityData)
    {
        System.out.println(entityData);
        if(allEntityData.containsKey(entityData) || allEntityData.containsValue(entityData))
        {
            System.out.println("ENTITYDOESEXISTINARRAY :)");
            return true;
        }
        System.out.println("ENTITY DOES NOT EXIXT IN ARRAY!  :(");
        return false;
    }

    @Override
    public String toString() 
    {
        return allEntityData.toString();
    }

}

---

具体来说，doesEntityExist总是返回false。数据确实存在于数组中，但由于某种原因，它仍然返回false。有什么想法吗？

当你观察到这种行为时，你从哪里调用

doesEntityExist

以及你传递给它的是什么？请粘贴你的代码，调用doesEntityExist总是返回false。我运行了一个示例，它将返回true。代码如下：StringArrayHolder=new StringArrayHolder（新字符串[]{“Hello”，“Java”}）；PathingData数据=新的PathingData（）；数据。附录（持有人）；System.out.println（data.doesEntityExist（holder））；您的数组仍然是可变的（即可以由客户端更改）。如果这是真的，那么这可以解释为什么doesEntityExist返回false。至少，您应该在构造函数中创建入站数组的副本，而不是保存引用。另外，您有多确定数组的成员是不可变的？如果它们的哈希代码可以更改，那么数组持有者的哈希代码也会更改。我添加了调用doesEntityExist的代码。您是否知道并同意这样一个事实，即执行

someStringArrayHolder.getData（）[0]=“blah”是否将更改内部阵列？
package timeTraveler.entities;

import java.util.Random;
import java.util.UUID;

import timeTraveler.core.StringArrayHolder;
import timeTraveler.core.TimeTraveler;
import timeTraveler.gui.GuiTimeTravel;

import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLiving;
import net.minecraft.entity.passive.EntityWolf;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraftforge.event.ForgeSubscribe;
import net.minecraftforge.event.entity.EntityJoinWorldEvent;

public class EntityHandler 
{
    boolean inPast;

    @ForgeSubscribe
    public void onEntityJoin(EntityJoinWorldEvent event)
    {

        inPast = GuiTimeTravel.isInPast;

        if(event.entity instanceof EntityLiving && !(event.entity instanceof EntityPlayer))
        {
            NBTTagCompound entityData = event.entity.getEntityData();
            Random rand = new Random();

            if(entityData.getInteger("identifier") == 0)
            {
                entityData.setInteger("identifier", rand.nextInt());
            }

            String[] data = new String[2];

            String identifier = Integer.toString(event.entity.getEntityData().getInteger("identifier"));
            String entityName = event.entity.getEntityName();

            data[0] = identifier;
            data[1] = entityName;

            StringArrayHolder d = new StringArrayHolder(data);

            if(inPast)
            {
                System.out.println(data[0]);
                System.out.println(data[1]);
                System.out.println(d);
                if(!TimeTraveler.vars.pathData.doesEntityExist(d))
                {
                    System.out.println("REMOVING ENTITY");

                    //event.entity.setDead();
                }
                else
                {
                    System.out.println(":)");
                }
            }
        }
    }

}