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mzcydev/UUIDFetcher.java

Created June 12, 2025 18:37
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Simple, new uuid fetcher.
Raw
UUIDFetcher.java
package dev.mzcy.util;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonNull;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import lombok.AccessLevel;
import lombok.NonNull;
import lombok.experimental.FieldDefaults;
import lombok.experimental.UtilityClass;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import java.io.FileNotFoundException;
import java.net.SocketException;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.util.LinkedList;
import java.util.List;
import java.util.Locale;
import java.util.UUID;
import java.util.concurrent.CompletableFuture;
import java.util.function.Function;
import java.util.regex.Pattern;
@UtilityClass
@FieldDefaults(level = AccessLevel.PRIVATE, makeFinal = true)
public class UUIDFetcher {
Cache<String, UUID> NAME_TO_UNIQUE_ID_CACHE = CacheBuilder.newBuilder().expireAfterWrite(Duration.ofDays(5)).build();
Cache<UUID, String> UNIQUE_ID_TO_NAME_CACHE = CacheBuilder.newBuilder().expireAfterWrite(Duration.ofDays(5)).build();
List<Function<String, UUID>> NAME_TO_UNIQUE_ID_CONVERTER_LIST = new LinkedList<>();
List<Function<UUID, String>> UNIQUE_ID_TO_NAME_CONVERTER_LIST = new LinkedList<>();
HttpClient HTTP_CLIENT = HttpClient.newHttpClient();
public void addNameToUniqueIdConverter(Function<String, UUID> function) {
NAME_TO_UNIQUE_ID_CONVERTER_LIST.add(function);
}
public void addUniqueIdToNameConverter(Function<UUID, String> function) {
UNIQUE_ID_TO_NAME_CONVERTER_LIST.add(function);
}
public CompletableFuture<UUID> getUniqueIdAsync(@NonNull String userName) {
return CompletableFuture.supplyAsync(() -> getUniqueId(userName));
}
public CompletableFuture<String> getUserNameAsync(@NonNull UUID uniqueId) {
return CompletableFuture.supplyAsync(() -> getUserName(uniqueId));
}
public @Nullable UUID getUniqueId(@NotNull String userName) {
if (!isValidMinecraftUserName(userName)) {
return null;
}
userName = userName.toLowerCase(Locale.ROOT);
UUID uniqueId = NAME_TO_UNIQUE_ID_CACHE.getIfPresent(userName);
if (uniqueId != null) {
return uniqueId;
}
for (Function<String, UUID> function : NAME_TO_UNIQUE_ID_CONVERTER_LIST) {
uniqueId = function.apply(userName);
if (uniqueId == null) {
continue;
}
NAME_TO_UNIQUE_ID_CACHE.put(userName, uniqueId);
return uniqueId;
}
String[] data = getRemoteUserData(userName);
if (data != null && data.length == 2) {
uniqueId = UUID.fromString(data[1]);
NAME_TO_UNIQUE_ID_CACHE.put(userName, uniqueId);
return uniqueId;
}
return null;
}
public @Nullable String getUserName(@NonNull UUID uniqueId) {
String name = UNIQUE_ID_TO_NAME_CACHE.getIfPresent(uniqueId);
if (name != null) {
return name;
}
for (Function<UUID, String> function : UNIQUE_ID_TO_NAME_CONVERTER_LIST) {
name = function.apply(uniqueId);
if (name == null) {
continue;
}
UNIQUE_ID_TO_NAME_CACHE.put(uniqueId, name);
return name;
}
String[] data = getRemoteUserData(uniqueId.toString());
if (data != null && data.length == 2) {
name = data[0];
UNIQUE_ID_TO_NAME_CACHE.put(uniqueId, name);
return name;
}
return null;
}
private String[] getRemoteUserData(@NotNull String nameOrUuid) {
try {
String url = "https://api.minetools.eu/uuid/" + nameOrUuid;
HttpRequest request = HttpRequest.newBuilder()
.GET()
.uri(URI.create(url))
.setHeader("User-Agent", "UUIDUtils-1.1")
.build();
String result = HTTP_CLIENT.send(request, HttpResponse.BodyHandlers.ofString()).body();
if (result == null || result.isEmpty() || result.trim().isEmpty()) {
return null;
}
JsonObject object = JsonParser.parseString(result).getAsJsonObject();
if (object == null || !object.has("name") || !object.has("id")) {
return null;
}
JsonElement uuidElement = object.get("id");
if (uuidElement == null || uuidElement instanceof JsonNull) {
return null;
}
String uniqueIdString = object.get("id").getAsString();
UUID uniqueId = validateUniqueId(uniqueIdString);
if (uniqueId == null) {
return null;
}
String name = object.get("name").getAsString();
return new String[]{name, uniqueId.toString()};
} catch (Exception e) {
if (!(e instanceof FileNotFoundException) && !(e instanceof SocketException)) {
throw new RuntimeException("Couldn't find uuid of \"" + nameOrUuid + "\" at api.minetools.eu:", e);
}
}
return null;
}
private @Nullable UUID validateUniqueId(@NotNull String string) {
if (string.length() != 32) {
return null;
}
if (string.contains("-")) {
return UUID.fromString(string);
}
String firstSeg = string.substring(0, 8); // 8
String secondSeg = string.substring(8, 12); // 4
String thirdSeg = string.substring(12, 16); // 4
String fourthSeg = string.substring(16, 20); // 4
String fifthSeg = string.substring(20, 32); // 12
return UUID.fromString(
firstSeg + "-" + secondSeg + "-" + thirdSeg + "-" + fourthSeg + "-" + fifthSeg);
}
private boolean isValidMinecraftUserName(@NotNull String userName) {
return Pattern.matches("^[a-zA-Z0-9_]{1}[a-zA-Z0-9_\\\\-]*$", userName);
}
}
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