pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.redrield</groupId>
    <artifactId>QrTest</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>QrTest</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <build>
        <defaultGoal>clean package</defaultGoal>
        <plugins>
            <plugin>
                <version>3.6.1</version>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>3.0.0</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                            <minimizeJar>true</minimizeJar>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
        </plugins>
        <resources>
            <resource>
                <directory>src/main/resources</directory>
                <filtering>true</filtering>
            </resource>
        </resources>
    </build>

    <repositories>
        <repository>
            <id>spigotmc-repo</id>
            <url>https://hub.spigotmc.org/nexus/content/groups/public/</url>
        </repository>
        <repository>
            <id>sonatype</id>
            <url>https://oss.sonatype.org/content/groups/public/</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>org.spigotmc</groupId>
            <artifactId>spigot-api</artifactId>
            <version>1.12-R0.1-SNAPSHOT</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>com.google.zxing</groupId>
            <artifactId>javase</artifactId>
            <version>3.3.0</version>
        </dependency>
    </dependencies>
</project>

QrMap.java

/*
This Source Code Form is subject to the terms of the Mozilla
Public License, v. 2.0. If a copy of the MPL was not distributed
with this file, You can obtain one at https://mozilla.org/MPL/2.0.
 */

package com.redrield.qrtest;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.WriterException;
import com.google.zxing.client.j2se.MatrixToImageWriter;
import com.google.zxing.common.BitMatrix;
import org.bukkit.Bukkit;
import org.bukkit.Material;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.player.AsyncPlayerChatEvent;
import org.bukkit.inventory.ItemStack;
import org.bukkit.map.MapCanvas;
import org.bukkit.map.MapRenderer;
import org.bukkit.map.MapView;
import org.bukkit.plugin.java.JavaPlugin;

import java.io.UnsupportedEncodingException;

/**
@author Redrield
@date 16/06/2017
*/
public final class QrTest extends JavaPlugin implements Listener{

    @Override
    public void onEnable() {
        getServer().getPluginManager().registerEvents(this, this);

    }

    @EventHandler
    public void onPlayerChat(AsyncPlayerChatEvent e) {
        try {
            BitMatrix bm = makeQrCode();
            ItemStack mapItem = new ItemStack(Material.MAP);
            e.getPlayer().getInventory().setItemInMainHand(mapItem);
            MapView itemView = Bukkit.getMap(mapItem.getDurability());
            itemView.getRenderers().forEach(itemView::removeRenderer);
            itemView.addRenderer(new MapRenderer() {
                @Override
                public void render(MapView map, MapCanvas canvas, Player player) {
                    canvas.drawImage(0, 0, MatrixToImageWriter.toBufferedImage(bm));
                }
            });
        } catch (UnsupportedEncodingException | WriterException e1) {
            e1.printStackTrace();
        }
    }


    private BitMatrix makeQrCode() throws UnsupportedEncodingException, WriterException {
        return new MultiFormatWriter().encode("Hello",
                BarcodeFormat.QR_CODE, 128, 128);
    }
}