Java UTF-8字符转换问题求助：JSON字符串数组字符乱码

Hey there! I see you're dealing with garbled characters (like your example showing "A...") when fetching a JSON string array in Java. Let's get this sorted out quickly.

The Root Cause #

The core issue here is that your InputStreamReader is using the platform default character set instead of explicitly specifying UTF-8. Most APIs return responses in UTF-8, so not setting this causes the decoder to misinterpret the raw byte data, leading to those messy garbled characters.

The Simple Fix #

You just need to modify the InputStreamReader initialization to explicitly use UTF-8. Java 7+ provides StandardCharsets.UTF_8—a safe, constant way to specify this (no risk of typos from using string literals like "UTF-8").

Here's your updated code with the fix highlighted:

import java.nio.charset.StandardCharsets; // Don't forget this import!

private static void loadProperties() throws Exception {
    String properties = null;
    HttpsURLConnection con = (HttpsURLConnection) new URL(getEndpoint()).openConnection();
    // Explicitly set UTF-8 to decode the response correctly
    BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream(), StandardCharsets.UTF_8));
    String inputLine;
    StringBuffer res = new StringBuffer();
    while((inputLine = in.readLine()) != null) {
        res.append(inputLine);
    }
    in.close();
    JsonObject jsonObject = new JsonParser().parse(res.toString()).getAsJsonObject();
    if(jsonObject.has("error")) {
        JsonObject error = jsonObject.get("error").getAsJsonObject();
        if(error.has("errorCode") && "1000".equals(error.get("errorCode").getAsString()) && jsonObject.has("data")) {
            properties = jsonObject.get("data").getAsJsonArray().toString();
            log("PropertiesUtils.loadProperties: Properties = %s", properties);
            setProperties(properties);
        } else {
            throw new Exception("PropertiesUtils.loadProperties: Error while calling properties endpoint");
        }
    } else {
        throw new Exception("PropertiesUtils.loadProperties: Error while calling properties endpoint");
    }
}

Bonus: Avoid Resource Leaks with Try-With-Resources #

To make your code more robust (and prevent leftover open streams/connections if an exception occurs), wrap your resources in a try-with-resources block. It automatically closes resources for you:

private static void loadProperties() throws Exception {
    String properties = null;
    // Auto-close connection and reader when block exits
    try (HttpsURLConnection con = (HttpsURLConnection) new URL(getEndpoint()).openConnection();
         BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream(), StandardCharsets.UTF_8))) {
        
        String inputLine;
        StringBuffer res = new StringBuffer();
        while((inputLine = in.readLine()) != null) {
            res.append(inputLine);
        }
        
        JsonObject jsonObject = new JsonParser().parse(res.toString()).getAsJsonObject();
        if(jsonObject.has("error")) {
            JsonObject error = jsonObject.get("error").getAsJsonObject();
            if(error.has("errorCode") && "1000".equals(error.get("errorCode").getAsString()) && jsonObject.has("data")) {
                properties = jsonObject.get("data").getAsJsonArray().toString();
                log("PropertiesUtils.loadProperties: Properties = %s", properties);
                setProperties(properties);
            } else {
                throw new Exception("PropertiesUtils.loadProperties: Error while calling properties endpoint");
            }
        } else {
            throw new Exception("PropertiesUtils.loadProperties: Error while calling properties endpoint");
        }
    }
}

That should resolve the garbled character issue completely. Let me know if you hit any other snags!

内容的提问来源于stack exchange，提问作者user8058277