Please follow the below steps to solve this problem, I solved the same issue
Some properties will not directly accessible to app layer in android, It is need to load the package dynamically, for that need to create a class SystemPropertiesProxy
Copy the below code as it is in SystemPropertiesProxy.java
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Some properties will not directly accessible to app layer in android, It is need to load the package dynamically, for that need to create a class SystemPropertiesProxy
Copy the below code as it is in SystemPropertiesProxy.java
package com.example.packname;
import java.io.File;
import java.lang.reflect.Method;
import android.content.Context;
import dalvik.system.DexFile;
public class SystemPropertiesProxy
{
/**
 * This class cannot be instantiated
 */
private SystemPropertiesProxy(){
}
    /**
     * Get the value for the given key.
     * @return an empty string if the key isn't found
     * @throws IllegalArgumentException if the key exceeds 32 characters
     */
    public static String get(Context context, String key) throws IllegalArgumentException {
        String ret= "";
        try{
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
          Class SystemProperties = cl.loadClass("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[1];
          paramTypes[0]= String.class;
          Method get = SystemProperties.getMethod("get", paramTypes);
          //Parameters
          Object[] params= new Object[1];
          params[0]= new String(key);
          ret= (String) get.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            ret= "";
            //TODO
        }
        return ret;
    }
    /**
     * Get the value for the given key.
     * @return if the key isn't found, return def if it isn't null, or an empty string otherwise
     * @throws IllegalArgumentException if the key exceeds 32 characters
     */
    public static String get(Context context, String key, String def) throws IllegalArgumentException {
        String ret= def;
        try{
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
          Class SystemProperties = cl.loadClass("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[2];
          paramTypes[0]= String.class;
          paramTypes[1]= String.class;         
          Method get = SystemProperties.getMethod("get", paramTypes);
          //Parameters
          Object[] params= new Object[2];
          params[0]= new String(key);
          params[1]= new String(def);
          ret= (String) get.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            ret= def;
            //TODO
        }
        return ret;
    }
    /**
     * Get the value for the given key, and return as an integer.
     * @param key the key to lookup
     * @param def a default value to return
     * @return the key parsed as an integer, or def if the key isn't found or
     *         cannot be parsed
     * @throws IllegalArgumentException if the key exceeds 32 characters
     */
    public static Integer getInt(Context context, String key, int def) throws IllegalArgumentException {
        Integer ret= def;
        try{
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
          Class SystemProperties = cl.loadClass("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[2];
          paramTypes[0]= String.class;
          paramTypes[1]= int.class; 
          Method getInt = SystemProperties.getMethod("getInt", paramTypes);
          //Parameters
          Object[] params= new Object[2];
          params[0]= new String(key);
          params[1]= new Integer(def);
          ret= (Integer) getInt.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            ret= def;
            //TODO
        }
        return ret;
    }
    /**
     * Get the value for the given key, and return as a long.
     * @param key the key to lookup
     * @param def a default value to return
     * @return the key parsed as a long, or def if the key isn't found or
     *         cannot be parsed
     * @throws IllegalArgumentException if the key exceeds 32 characters
     */
    public static Long getLong(Context context, String key, long def) throws IllegalArgumentException {
        Long ret= def;
        try{
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
              Class SystemProperties= cl.loadClass("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[2];
          paramTypes[0]= String.class;
          paramTypes[1]= long.class; 
          Method getLong = SystemProperties.getMethod("getLong", paramTypes);
          //Parameters
          Object[] params= new Object[2];
          params[0]= new String(key);
          params[1]= new Long(def);
          ret= (Long) getLong.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            ret= def;
            //TODO
        }
        return ret;
    }
    /**
     * Get the value for the given key, returned as a boolean.
     * Values 'n', 'no', '0', 'false' or 'off' are considered false.
     * Values 'y', 'yes', '1', 'true' or 'on' are considered true.
     * (case insensitive).
     * If the key does not exist, or has any other value, then the default
     * result is returned.
     * @param key the key to lookup
     * @param def a default value to return
     * @return the key parsed as a boolean, or def if the key isn't found or is
     *         not able to be parsed as a boolean.
     * @throws IllegalArgumentException if the key exceeds 32 characters
     */
    public static Boolean getBoolean(Context context, String key, boolean def) throws IllegalArgumentException {
        Boolean ret= def;
        try{
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
          Class SystemProperties = cl.loadClass("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[2];
          paramTypes[0]= String.class;
          paramTypes[1]= boolean.class; 
          Method getBoolean = SystemProperties.getMethod("getBoolean", paramTypes);
          //Parameters       
          Object[] params= new Object[2];
          params[0]= new String(key);
          params[1]= new Boolean(def);
          ret= (Boolean) getBoolean.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            ret= def;
            //TODO
        }
        return ret;
    }
    /**
     * Set the value for the given key.
     * @throws IllegalArgumentException if the key exceeds 32 characters
     * @throws IllegalArgumentException if the value exceeds 92 characters
     */
    public static void set(Context context, String key, String val) throws IllegalArgumentException {
        try{
          @SuppressWarnings("unused")
          DexFile df = new DexFile(new File("/system/app/Settings.apk"));
          @SuppressWarnings("unused")
          ClassLoader cl = context.getClassLoader();
          @SuppressWarnings("rawtypes")
          Class SystemProperties = Class.forName("android.os.SystemProperties");
          //Parameters Types
          @SuppressWarnings("rawtypes")
              Class[] paramTypes= new Class[2];
          paramTypes[0]= String.class;
          paramTypes[1]= String.class; 
          Method set = SystemProperties.getMethod("set", paramTypes);
          //Parameters       
          Object[] params= new Object[2];
          params[0]= new String(key);
          params[1]= new String(val);
          set.invoke(SystemProperties, params);
        }catch( IllegalArgumentException iAE ){
            throw iAE;
        }catch( Exception e ){
            //TODO
        }
    }
}
Calling in your code
String property = SystemPropertiesProxy.get(this, "sys.boot_completed");
Thus your problem gets solved.
