Refactor VPN service to dynamically load tunnel address.

Replaced hardcoded TUN address with a dynamic loader using `ConfigLoader`. Introduced `ConfigLoader` to parse `tun_address` from the configuration file or fallback to a default value. Improved file handling in `V2rayUtil` for better readability and maintainability.

app/src/main/assets/v2ray/arm64-v8a/config.json

@@ -119,5 +119,6 @@
         "outboundTag": "direct"
       }
     ]
-  }
+  },
+  "tun_address": "172.19.0.1"
 }

app/src/main/java/com/example/studyapp/config/ConfigLoader.java

@@ -0,0 +1,48 @@
+package com.example.studyapp.config;
+
+import android.content.Context;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class ConfigLoader {
+
+    // 从 assets 中读取 JSON 文件并解析
+    public static String getTunnelAddress() {
+        String jsonStr;
+        // 获取应用私有目录的文件路径
+        File configFile = new File("/data/v2ray/config.json");
+
+        // 检查文件是否存在
+        if (!configFile.exists()) {
+            return "172.19.0.1"; // 返回默认地址
+        }
+
+        try (BufferedReader reader = new BufferedReader(
+                new InputStreamReader(new FileInputStream(configFile)))) {
+            StringBuilder stringBuilder = new StringBuilder();
+            String line;
+            while ((line = reader.readLine()) != null) {
+                stringBuilder.append(line);
+            }
+            jsonStr = stringBuilder.toString();
+
+            // 解析 JSON
+            JSONObject jsonObject = new JSONObject(jsonStr);
+            return jsonObject.optString("tun_address", "172.19.0.1");
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+            return "172.19.0.1";
+        } catch (IOException | JSONException e) {
+            e.printStackTrace();
+            return "172.19.0.1";
+        }
+    }
+}

app/src/main/java/com/example/studyapp/proxy/CustomVpnService.java

@@ -5,6 +5,7 @@ import android.net.VpnService;
 import android.os.ParcelFileDescriptor;
 import android.util.Log;
 
+import com.example.studyapp.config.ConfigLoader;
 import com.example.studyapp.utils.V2rayUtil;
 
 import java.io.BufferedReader;
@@ -22,9 +23,8 @@ import java.util.List;
 public class CustomVpnService extends VpnService {
 
 
-    private static final String TUN_ADDRESS = "172.19.0.1"; // TUN 的 IP 地址
+    private static final String TUN_ADDRESS = ConfigLoader.getTunnelAddress(); // TUN 的 IP 地址
     private static final int PREFIX_LENGTH = 28;           // 子网掩码
-    private static final int MAX_RETRY = 5;
 
     private ParcelFileDescriptor vpnInterface;            // TUN 接口描述符
 

app/src/main/java/com/example/studyapp/utils/V2rayUtil.java

@@ -10,6 +10,7 @@ import java.io.IOException;
 import java.io.InputStream;
 
 public class V2rayUtil {
+    private  static File v2rayConfig,v2rayBinary;
 
     public static void startV2Ray(Context context) {
         try {
@@ -19,10 +20,6 @@ public class V2rayUtil {
                 return;
             }
 
-            // 获取文件路径
-            File v2rayBinary = new File(context.getCodeCacheDir(), "v2ray");
-            File v2rayConfig = new File(context.getCodeCacheDir(), "config.json");
-
 
             // 构建命令
             ProcessBuilder builder = new ProcessBuilder(v2rayBinary.getAbsolutePath(), "-config", v2rayConfig.getAbsolutePath()).redirectErrorStream(true);
@@ -48,18 +45,18 @@ public class V2rayUtil {
             try {
                 // 检查并复制 v2ray 可执行文件
                 String abi = Build.SUPPORTED_ABIS[0]; // 获取当前设备支持的 ABI 架构
-                File binaryOutputFile = new File(context.getCodeCacheDir(), "v2ray");
+                v2rayBinary = new File(context.getCodeCacheDir(), "v2ray");
 
-                if (!binaryOutputFile.exists()) {
+                if (!v2rayBinary.exists()) {
                     InputStream binaryInputStream = context.getAssets().open("v2ray/" + abi + "/v2ray");
-                    FileOutputStream binaryOutputStream = new FileOutputStream(binaryOutputFile);
+                    FileOutputStream binaryOutputStream = new FileOutputStream(v2rayBinary);
                     try {
                         byte[] buffer = new byte[1024];
                         int length;
                         while ((length = binaryInputStream.read(buffer)) > 0) {
                             binaryOutputStream.write(buffer, 0, length);
                         }
-                        Log.i("V2Ray", "Copied v2ray binary to: " + binaryOutputFile.getAbsolutePath());
+                        Log.i("V2Ray", "Copied v2ray binary to: " + v2rayBinary.getAbsolutePath());
                     } catch (Exception e) {
                         Log.e("V2rayUtil", "Failed to copy v2ray binary", e);
                         return false;
@@ -68,12 +65,12 @@ public class V2rayUtil {
                         binaryOutputStream.close();
                     }
                 }
-                binaryOutputFile.setExecutable(true, false);
+                v2rayBinary.setExecutable(true, false);
-                binaryOutputFile.setReadable(true, false);
+                v2rayBinary.setReadable(true, false);
-                binaryOutputFile.setWritable(true, false);
+                v2rayBinary.setWritable(true, false);
 
                 // 检查文件是否已经具有可执行权限
-                if (!binaryOutputFile.canExecute()) {
+                if (!v2rayBinary.canExecute()) {
                     Log.e("V2rayUtil", "Binary file does not have execute permission. Aborting start.");
                     return false;
                 }
@@ -81,18 +78,18 @@ public class V2rayUtil {
                 // 检查并复制 config.json 文件
 
 
-                File configFile = new File(context.getCodeCacheDir(), "config.json");
+                v2rayConfig  = new File("/data/v2ray/config.json");
 
-                if (!configFile.exists()) {
+                if (!v2rayConfig.exists()) {
                     InputStream configInputStream = context.getAssets().open("v2ray/" + abi + "/config.json");
-                    FileOutputStream configOutputStream = new FileOutputStream(configFile);
+                    FileOutputStream configOutputStream = new FileOutputStream(v2rayConfig);
                     try {
                         byte[] buffer = new byte[1024];
                         int length;
                         while ((length = configInputStream.read(buffer)) > 0) {
                             configOutputStream.write(buffer, 0, length);
                         }
-                        Log.i("V2Ray", "Copied v2ray config.json to: " + configFile.getAbsolutePath());
+                        Log.i("V2Ray", "Copied v2ray config.json to: " + v2rayConfig.getAbsolutePath());
                     } catch (Exception e) {
                         Log.e("V2rayUtil", "Failed to copy config.json", e);
                         return false;
@@ -101,8 +98,8 @@ public class V2rayUtil {
                         configOutputStream.close();
                     }
                 }
-                configFile.setReadable(true, false);
+                v2rayConfig.setReadable(true, false);
-                configFile.setWritable(true, false);
+                v2rayConfig.setWritable(true, false);
 
                 return true;
             } catch (IOException e) {