pocketcommunityclient/app/src/main/java/com/community/pocket/data/login/Result.java

package com.community.pocket.data.login;

import org.jetbrains.annotations.NotNull;

/**
 * A generic class that holds a result success w/ data or an error exception.
 * 一个泛型类，它持有一个结果成功w/数据或一个错误异常。
 */
public class Result<T> {
    // hide the private constructor to limit subclass types (Success, Error)
    private Result() {
    }

    @NotNull
    @Override
    public String toString() {
        if (this instanceof Result.Success) {
            Result.Success success = (Result.Success) this;
            return "Success[data=" + success.getData().toString() + "]";
        } else if (this instanceof Result.Error) {
            Result.Error error = (Result.Error) this;
            return "Error[exception=" + error.getError().toString() + "]";
        }
        return "";
    }

    // Success sub-class
    public final static class Success<T> extends Result<T> {
        private T data;

        Success(T data) {
            this.data = data;
        }

        public T getData() {
            return this.data;
        }
    }

    // Error sub-class
    final static class Error<T> extends Result<T> {
        private Exception error;
        private Class<T> c;

        Error(Exception error, Class<T> c) {
            this.error = error;
            this.c = c;
        }

        Exception getError() {
            return this.error;
        }

        public Class<T> getC() {
            return c;
        }
    }
}