Fixed: Fix NullPointerException in BatteryStatusAPI while converting a null Integer to an int for batteryCurrentNow and also do not output null values

```
java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.Integer.intValue()' on a null object reference
    at com.termux.api.apis.BatteryStatusAPI$1.writeJson(SourceFile:138)
    at com.termux.api.util.ResultReturner$ResultJsonWriter.writeResult(SourceFile:169)
    at com.termux.api.util.ResultReturner.lambda$returnData$0(SourceFile:271)
    at com.termux.api.util.ResultReturner.$r8$lambda$RFR2zSHu5FsJH7JvuCx4CPnUmMY(SourceFile:0)
    at com.termux.api.util.ResultReturner$$ExternalSyntheticLambda0.run(SourceFile:0)
    at java.lang.Thread.run(Thread.java:1119)
    Suppressed: java.lang.Exception: Called by:
        at com.termux.api.util.ResultReturner.returnData(SourceFile:239)
        at com.termux.api.apis.BatteryStatusAPI.onReceive(SourceFile:27)
        at com.termux.api.TermuxApiReceiver.doWork(SourceFile:91)
        at com.termux.api.TermuxApiReceiver.onReceive(SourceFile:65)
        at android.app.ActivityThread.handleReceiver(ActivityThread.java:4458)
        at android.app.ActivityThread.access$1800(ActivityThread.java:277)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2172)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loopOnce(Looper.java:210)
        at android.os.Looper.loop(Looper.java:299)
        at android.app.ActivityThread.main(ActivityThread.java:8298)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:576)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1073)
```

Author: agnostic-apollo

app/src/main/java/com/termux/api/apis/BatteryStatusAPI.java

@@ -1,5 +1,7 @@
 package com.termux.api.apis;
 
+import static com.termux.api.util.JsonUtils.*;
+
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.Intent;
@@ -30,6 +32,7 @@ public static void onReceive(TermuxApiReceiver apiReceiver, final Context contex
             public void writeJson(JsonWriter out) throws Exception {
                 // - https://cs.android.com/android/platform/superproject/+/android-15.0.0_r1:frameworks/base/services/core/java/com/android/server/BatteryService.java;l=745
                 Intent batteryStatus = context.registerReceiver(null, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
+                if (batteryStatus == null) batteryStatus = new Intent();
 
                 int batteryLevel = batteryStatus.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
                 int batteryScale = batteryStatus.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
@@ -135,38 +138,40 @@ public void writeJson(JsonWriter out) throws Exception {
                 // charger does not output enough current, and will result in false inversions.
                 // - https://developer.android.com/reference/android/os/BatteryManager#BATTERY_PROPERTY_CURRENT_NOW
                 // - https://issuetracker.google.com/issues/37131318
-                int batteryCurrentNow = getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CURRENT_NOW);
+                Integer batteryCurrentNow = getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CURRENT_NOW);
 
                 // - https://stackoverflow.com/questions/64532112/batterymanagers-battery-property-current-now-returning-0-or-incorrect-current-v
-                if (Math.abs(batteryCurrentNow / 1000) < 1.0) {
+                if (batteryCurrentNow != null && Math.abs(batteryCurrentNow / 1000) < 1.0) {
                     Logger.logVerbose(LOG_TAG, "Fixing current_now from " + batteryCurrentNow + " to " + (batteryCurrentNow * 1000));
                     batteryCurrentNow = batteryCurrentNow * 1000;
                 }
 
                 out.beginObject();
-                out.name("present").value(batteryStatus.getBooleanExtra(BatteryManager.EXTRA_PRESENT, false));
-                out.name("technology").value(batteryStatus.getStringExtra(BatteryManager.EXTRA_TECHNOLOGY));
-                out.name("health").value(batteryHealth);
-                out.name("plugged").value(batteryPlugged);
-                out.name("status").value(batteryStatusString);
-                out.name("temperature").value(batteryTemperature);
-                out.name("voltage").value(batteryVoltage);
-                out.name("current").value(batteryCurrentNow);
-                out.name("current_average").value(getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CURRENT_AVERAGE));
-                out.name("percentage").value(getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CAPACITY));
-                out.name("level").value(batteryLevel);
-                out.name("scale").value(batteryScale);
-                out.name("charge_counter").value(getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CHARGE_COUNTER));
-                out.name("energy").value(getLongProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_ENERGY_COUNTER));
+                putBooleanValueIfSet(out, "present", batteryStatus.getBooleanExtra(BatteryManager.EXTRA_PRESENT, false));
+                putStringIfSet(out, "technology", batteryStatus.getStringExtra(BatteryManager.EXTRA_TECHNOLOGY));
+                putStringIfSet(out, "health", batteryHealth);
+                putStringIfSet(out, "plugged", batteryPlugged);
+                putStringIfSet(out, "status", batteryStatusString);
+                putDoubleIfSet(out, "temperature", batteryTemperature);
+                putIntegerIfSet(out, "voltage", batteryVoltage);
+                putIntegerIfSet(out, "current", batteryCurrentNow);
+                putIntegerIfSet(out, "current_average", getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CURRENT_AVERAGE));
+                putIntegerIfSet(out, "percentage", getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CAPACITY));
+                putIntegerIfSet(out, "level", batteryLevel);
+                putIntegerIfSet(out, "scale", batteryScale);
+                putIntegerIfSet(out, "charge_counter", getIntProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_CHARGE_COUNTER));
+                putLongIfSet(out, "energy", getLongProperty(batteryManager, BatteryManager.BATTERY_PROPERTY_ENERGY_COUNTER));
                 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.UPSIDE_DOWN_CAKE) {
                     int batteryCycle = batteryStatus.getIntExtra(BatteryManager.EXTRA_CYCLE_COUNT, -1);
-                    out.name("cycle").value(batteryCycle != -1 ? batteryCycle : null);
+                    putIntegerIfSet(out, "cycle", batteryCycle != -1 ? batteryCycle : null);
                 }
                 out.endObject();
             }
         });
     }
 
+
+
     /**
      * - https://developer.android.com/reference/android/os/BatteryManager.html#getIntProperty(int)
      */
@@ -187,4 +192,5 @@ private static Long getLongProperty(BatteryManager batteryManager, int id) {
         long value = batteryManager.getLongProperty(id);
         return value != Long.MIN_VALUE ? value : null;
     }
+
 }

app/src/main/java/com/termux/api/util/JsonUtils.java

@@ -0,0 +1,65 @@
+package com.termux.api.util;
+
+import android.util.JsonWriter;
+
+import com.termux.shared.logger.Logger;
+
+import java.io.IOException;
+
+public class JsonUtils {
+
+    public static final String LOG_TAG = "JsonUtils";
+
+
+
+    public static void putBooleanValueIfSet(JsonWriter out, String key, Boolean value) {
+        if (out == null || key == null || key.isEmpty() || value == null) return;
+
+        try {
+            out.name(key).value(value);
+        } catch (IOException e) {
+            Logger.logStackTraceWithMessage(LOG_TAG, "Failed to put \"" + key + "\" with boolean value \"" + value + "\"", e);
+        }
+    }
+
+    public static void putIntegerIfSet(JsonWriter out, String key, Integer value) {
+        if (out == null || key == null || key.isEmpty() || value == null) return;
+
+        try {
+            out.name(key).value(value);
+        } catch (IOException e) {
+            Logger.logStackTraceWithMessage(LOG_TAG, "Failed to put \"" + key + "\" with integer value \"" + value + "\"", e);
+        }
+    }
+
+    public static void putLongIfSet(JsonWriter out, String key, Long value) {
+        if (out == null || key == null || key.isEmpty() || value == null) return;
+
+        try {
+            out.name(key).value(value);
+        } catch (IOException e) {
+            Logger.logStackTraceWithMessage(LOG_TAG, "Failed to put \"" + key + "\" with long value \"" + value + "\"", e);
+        }
+    }
+
+    public static void putDoubleIfSet(JsonWriter out, String key, Double value) {
+        if (out == null || key == null || key.isEmpty() || value == null) return;
+
+        try {
+            out.name(key).value(value);
+        } catch (IOException e) {
+            Logger.logStackTraceWithMessage(LOG_TAG, "Failed to put \"" + key + "\" with double value \"" + value + "\"", e);
+        }
+    }
+
+    public static void putStringIfSet(JsonWriter out, String key, String value) {
+        if (out == null || key == null || key.isEmpty() || value == null) return;
+
+        try {
+            out.name(key).value(value);
+        } catch (IOException e) {
+            Logger.logStackTraceWithMessage(LOG_TAG, "Failed to put \"" + key + "\" with string value \"" + value + "\"", e);
+        }
+    }
+
+}