记录一下项目用到的工具类
import android.content.Context; import java.lang.reflect.Method; public class SystemPropertyUtil { /** * 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("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 } } }
标签：String,SystemProperties,paramTypes,params,key,android,os,def From： https://www.cnblogs.com/mhzf/p/17036942.html