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How do I change the value of a java Path object?

Below, I am trying to change the value of the Path object there using the setSoundPath() method. I cannot find any documentation to say this is possible.
I am trying to create a class that will create a copy of a file at a specified path and put the copy in the specified folder. I need to be able to change the name of the path though, because I want to create the sound object with an initial placeholder file path.
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.*;
import java.io.IOException;
import javafx.beans.property.StringProperty;
import javafx.beans.property.SimpleStringProperty;
class Scratch {
public static class Sound extends Object{
private Path there;
StringProperty tests = new SimpleStringProperty(this, "test", "");
public Sound(){
this.there = Paths.get("C:\\Users\\HNS1Lab.NETWORK\\Videos\\JuiceWRLD.mp3");
}
public void setSoundPath(String SoundPath) {
this.tests.setValue(SoundPath);
this.there = Paths.get(this.tests.toString());
}
}
public static void main(String[] args) {
Sound test = new Sound();
test.setSoundPath("C:\\Users\\HNS1Lab.NETWORK\\Music\\Meowing-cat-sound.mp3");
test.copySound();
System.out.println("Path: " + test.getSoundPath().toString());
}
}

They are immutable:
Implementations of this interface are immutable and safe for use by
multiple concurrent threads.
(from: https://docs.oracle.com/javase/7/docs/api/java/nio/file/Path.html)
You can create new Path objects that point to your path.

IllegalArgumentException when using GSON's fromJson()

I have this exception when trying to parse a JSON file with GSON:
Exception in thread "JavaFX Application Thread" java.lang.IllegalArgumentException: class com.sun.javafx.jmx.HighlightRegion declares multiple JSON fields named hash
I have tested a little to what causes this, and I found that it only occurs when I create a Object that has an Event object as a member. In this case, I am trying to create a List of Quest objects that eventually have Event objects.
package Quests;
import Events.EventSequence;
import com.google.gson.Gson;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
public class Quest {
public static void parseQuest() {
Gson gson = new Gson();
FileReader questGSON;
try {
questGSON = new FileReader(QUEST_FILE);
} catch (FileNotFoundException e) {
e.printStackTrace();
return;
}
JsonObject questJSON = gson.fromJson(questGSON, JsonObject.class);
questList = new ArrayList<>();
for(Map.Entry<String, JsonElement> element : questJSON.entrySet()) {
questList.add(gson.fromJson(element.getValue(), Quest.class));
}
}
}
I am using javafx in that class in the following way:
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.control.Button;
public abstract class Event implements EventHandler<ActionEvent> {
// members of this class
private String title, text;
private Button[] buttonSet;
protected Entity other;
protected Event nextEvent;
public abstract Event chooseNewEvent(String command);
#Override
public void handle(ActionEvent event) {
// Get the name of the button
String command = ((Button) event.getSource()).getText();
displayNewEvent(chooseNewEvent(command));
}
}
The only information I could find regarding this was:
https://github.com/wpilibsuite/shuffleboard/issues/358
Could someone point me in some direction to fix my bug?

I found out that it was a Button array from javafx.scene.control.Button in my Event class that was causing the problem. I fixed it by making it transient so it would get ignored by GSON and not cause any problems.
Nevertheless, I have no idea why the Button array would cause this exception. Any thoughts?

Textures do not appear

I am trying to add a texture to an item, yet the texture just doesn't appear. I have the texture made, and in the right file directory, but while in game it doesn't display. Thus, I think it's an error in my code.
For the whole class file, see below:
package Moonstone;
import cpw.mods.fml.common.Mod;
import cpw.mods.fml.common.Mod.EventHandler;
import cpw.mods.fml.common.event.FMLInitializationEvent;
import cpw.mods.fml.common.event.FMLPostInitializationEvent;
import cpw.mods.fml.common.event.FMLPreInitializationEvent;
import cpw.mods.fml.common.registry.GameRegistry;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.init.Items;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraftforge.common.util.EnumHelper;
#Mod(modid = "ms", name = "Moonstone", version = "1.0")
public class MoonstoneMain {
public static Item moonstone;
#EventHandler
public void preInit(FMLPreInitializationEvent event) {
//All init
moonstone = new Moonstone().setUnlocalizedName("Moonstone").setTextureName("moonstone").setMaxStac kSize(64);
GameRegistry.registerItem(moonstone, moonstone.getUnlocalizedName().substring(5));
}
#EventHandler
public void init(FMLInitializationEvent event) {
//Proxy, TileEntity, entity, GUI and packet registering
}
#EventHandler
public void postInit(FMLPostInitializationEvent event) {
}
public static CreativeTabs tabMoonstone = new CreativeTabs("tabMoonstone"){
#Override
public Item getTabIconItem(){
return new ItemStack(Items.stick).getItem();
}
};
}
For just the item, look below-
moonstone = new Moonstone().setUnlocalizedName("Moonstone").setTextureName("moonstone").setMaxStackSize(64);// I have tried with ms:moonstone and without, both don't work.
GameRegistry.registerItem(moonstone, moonstone.getUnlocalizedName().substring(5));

Recommended changes but not necessary:
First:
When registering the item you should remove the .substring(5),
having this in will name the item "Moons" instead of "Moonstone".
Second:
unlocalized names should always be lowercase and should be formatted
as modid_itemname
Third:
Package names should be lowercase, package moonstone
Fourth:
Your should make a Refstrings.java file and put the modid, version and name in it
package Moonstone
public RefStrings{
public static String NAME = "Moonstone";
public static String MODID = "ms";
public static String VERSION = "1.0";
}
Necessary changes:
Your setTextureName should be passed "ms:moonstone"
You didn't post your folder structure but it should look like this:
src/main/java/Moonstone/MoonstoneMain.java
src/main/resources/assests/ms/textures/items/moonstone.png
it is possible that some of the recommend changes will be what fixes the problem, minecraft can be a bit finicky with naming.

Managing files in Java

I know C++ at a decent level and I am trying to learn java. This will be a silly question but I cannot figure out how to import a .java file into another. I am at Eclipse IDE and in my project I have two files:
FileReader.java
Entry.java
I want to import the Entry.java in the other file but no matter what I do I get an error. Can you help me? Thx in advance.
FileReader.java :
import java.io.*;
class FileReader {
public static void main(String[] args) throws Exception {
System.out.println("Hello, World");
Entry a(10,"a title","a description");
a.print();
}
}
Entry.java:
public class Entry{
int ID;
String title;
String description;
public Entry(int id, String t,String d){
ID=id;
title=t;
description=d;
}
public void print(){
System.out.println("ID:"+ID);
System.out.println("Title:"+title);
System.out.println("Description:"+description);
}
}
At this state I get an error that Entry cannot be resolved as a variable. So I believe that it is related to the import.

Firstly
Entry a(10,"a title","a description");
should be
Entry a = new Entry (10,"a title","a description");
If Entry is in the same package then you will not need to import it.
If Entry is in a different package, say com.example then you will need to do
Either
import com.example.Entry;
or
import com.example.*;
The second import will import all classes in the com.example package - usually not such a good thing.

You need new Entry
The new keyword creates the new object
Entry a = new Entry(10,"a title","a description")
a.print();
An Entry object is created with the a reference with the above instantiation.
For the import part of your question, if two files are in the same package, no import is needed. If you Entry class was in a different package than your FileReader class, then you would need to import mypackage.Entry

Try
Entry a = new Entry(/*args*/);
And if you need to import the class, then use the absolute name (package+class) and put it after import above the class declaration
import com.example.you.Entry;

In Eclipse you can do Ctrl+Shift+O to resolve all imports.

NullPointerException when adding keys in BloomFilter

I used the hadoop apache to create a counting Bloom Filter. However I get a NullPointerException when I am trying to add keys in it. I tried to change the class structure in many ways but still I get the same result.
Here is the code I did:
package package_name;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import org.apache.hadoop.util.bloom.*;
public class CBF {
public static CountingBloomFilter CBF = new CountingBloomFilter();
public static void countingFilter (ArrayList<byte[]> CBF_Keys) throws IOException{
CBF_Keys= Keys.keyStringArray;
Iterator<byte[]> iter = CBF_Keys.iterator();
while (iter.hasNext()) {
byte[] temp = iter.next();
Key hadoop_key = new Key(temp, 2.0);
CBF.add(hadoop_key);
}
}
}

problem is CBF = new CountingBloomFilter(). We should use CountingBloomFilter(int vectorSize, int nbHash, int hashType) instead here, otherwise the HashFunction will not be constructed in parent class Filter.