fix(multiplayer): show "failed to test" instead of "testing".

HMCLCore/src/main/java/org/jackhuang/hmcl/util/Result.java

@@ -0,0 +1,67 @@
+/*
+ * Hello Minecraft! Launcher
+ * Copyright (C) 2021  huangyuhui <huanghongxun2008@126.com> and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package org.jackhuang.hmcl.util;
+
+import java.util.Objects;
+
+public abstract class Result<T> {
+
+    public T get() {
+        throw new IllegalStateException("TriState not ok");
+    }
+
+    public boolean isOK() {
+        return false;
+    }
+
+    public boolean isError() {
+        return false;
+    }
+
+    public static <T> Result<T> ok(T result) {
+        return new OK<>(Objects.requireNonNull(result));
+    }
+
+    @SuppressWarnings("unchecked")
+    public static <T> Result<T> error() {
+        return (Result<T>) Error.INSTANCE;
+    }
+
+    private static class OK<T> extends Result<T> {
+        private final T result;
+
+        public OK(T result) {
+            this.result = result;
+        }
+
+        @Override
+        public T get() {
+            return result;
+        }
+    }
+
+    private static class Error<T> extends Result<T> {
+        public static final Error<Void> INSTANCE = new Error<>();
+
+        @Override
+        public boolean isError() {
+            return true;
+        }
+    }
+
+}