SystemPropertyUtils.java

package com.paike.zjc.utils;

import android.content.Context;

import com.paike.zjc.log.HLog;

import java.io.File;
import java.lang.reflect.Method;

import dalvik.system.DexFile;

public class SystemPropertyUtils {

	/**
	 * 根据给定Key获取值.
	 * 
	 * @return 如果不存在该key则返回空字符串
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[1];
			paramTypes[0] = String.class;

			Method get = SystemProperties.getMethod("get", paramTypes);

			// 参数
			Object[] params = new Object[1];
			params[0] = key;

			ret = (String) get.invoke(SystemProperties, params);
			

		} catch (IllegalArgumentException iAE) {
			throw iAE;
		} catch (Exception e) {
			ret = "";
			// TODO
		}

		return ret;

	}

	/**
	 * 根据Key获取值.
	 * 
	 * @return 如果key不存在, 并且如果def不为空则返回def否则返回空字符串
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[2];
			paramTypes[0] = String.class;
			paramTypes[1] = String.class;

			Method get = SystemProperties.getMethod("get", paramTypes);

			// 参数
			Object[] params = new Object[2];
			params[0] = key;
			params[1] = def;

			ret = (String) get.invoke(SystemProperties, params);
			

		} catch (IllegalArgumentException iAE) {
			throw iAE;
		} catch (Exception e) {
			ret = def;
			// TODO
		}

		return ret;

	}

	/**
	 * 根据给定的key返回int类型值.
	 * 
	 * @param key
	 *            要查询的key
	 * @param def
	 *            默认返回值
	 * @return 返回一个int类型的值, 如果没有发现则返回默认值
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[2];
			paramTypes[0] = String.class;
			paramTypes[1] = int.class;

			Method getInt = SystemProperties.getMethod("getInt", paramTypes);

			// 参数
			Object[] params = new Object[2];
			params[0] = 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;

	}

	/**
	 * 根据给定的key返回long类型值.
	 * 
	 * @param key
	 *            要查询的key
	 * @param def
	 *            默认返回值
	 * @return 返回一个long类型的值, 如果没有发现则返回默认值
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[2];
			paramTypes[0] = String.class;
			paramTypes[1] = long.class;

			Method getLong = SystemProperties.getMethod("getLong", paramTypes);

			// 参数
			Object[] params = new Object[2];
			params[0] = 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;

	}

	/**
	 * 根据给定的key返回boolean类型值. 如果值为 'n', 'no', '0', 'false' or 'off' 返回false.
	 * 如果值为'y', 'yes', '1', 'true' or 'on' 返回true. 如果key不存在, 或者是其它的值, 则返回默认值.
	 * 
	 * @param key
	 *            要查询的key
	 * @param def
	 *            默认返回值
	 * @return 返回一个boolean类型的值, 如果没有发现则返回默认值
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[2];
			paramTypes[0] = String.class;
			paramTypes[1] = boolean.class;

			Method getBoolean = SystemProperties.getMethod("getBoolean", paramTypes);

			// 参数
			Object[] params = new Object[2];
			params[0] = 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;

	}

	/**
	 * 根据给定的key和值设置属性, 该方法需要特定的权限才能操作.
	 * 
	 * @throws IllegalArgumentException
	 *             如果key超过32个字符则抛出该异常
	 * @throws IllegalArgumentException
	 *             如果value超过92个字符则抛出该异常
	 */
	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");

			// 参数类型
			@SuppressWarnings("rawtypes")
			Class[] paramTypes = new Class[2];
			paramTypes[0] = String.class;
			paramTypes[1] = String.class;

			Method set = SystemProperties.getMethod("set", paramTypes);

			// 参数
			Object[] params = new Object[2];
			params[0] = key;
			params[1] = val;

			set.invoke(SystemProperties, params);

		} catch (IllegalArgumentException iAE) {
			throw iAE;
		} catch (Exception e) {
			// TODO
		}

	}
}