android11系统的时候，默认静态IP设置很简单，修改frameworks\base\core\res\res\values\config.xml中的config_ethernet_interfaces字符数组，在里面添加静态IP的参数就可以了。
 

    <string-array translatable="false" name="config_ethernet_interfaces"><!--<item>eth1;12,13,14,15;ip=192.168.0.10/24 gateway=192.168.0.1 dns=4.4.4.4,8.8.8.8</item><item>eth2;;ip=192.168.0.11/24</item><item>eth3;12,13,14,15;ip=192.168.0.12/24;1</item>--></string-array>

android13以后，这个参数移动到了packages\modules\Connectivity\service\ServiceConnectivityResources\res\values\config.xml下面，修改以后以太网是能够默认静态IP，但是发现以太网上不了网了，设置动态IP也不行。很是奇怪。后面只能通过另外一种方式去设置，即开机启动的时候去设置一次静态IP。

具体使用如下几个函数：

	public void initEthIp(Context context){boolean issetIP = SystemProperties.getInt("persist.sys.eth_static_ip_flag", 0) == 1 ? true:false;if(issetIP){return;}if(setEthIPAddress(context, "192.168.1.2", "255.255.255.0", "192.168.1.200", "192.168.1.200","8.8.8.8")){SystemProperties.set("persist.sys.eth_static_ip_flag", "1");Log.d(TAG, "set static eth ip ok!");}else{Log.d(TAG, "set static eth ip failed!");}}public boolean setEthIPAddress(Context context, String IP, String Mask, String Gateway, String DNS, String DNS2){String Interface = "eth0";EthernetManager mEthManager;mEthManager = (EthernetManager) (EthernetManager)context.getSystemService(Context.ETHERNET_SERVICE);IpConfiguration.IpAssignment mIpAssignment = IpConfiguration.IpAssignment.DHCP;if (mEthManager != null) {if (isIpAddress(IP) && isIpAddress(Mask) && isIpAddress(Gateway)&& isIpAddress(DNS)) {StaticIpConfiguration mStaticIpConfiguration = new StaticIpConfiguration();if (validateIpConfigFields(mStaticIpConfiguration, IP, Mask,Gateway, DNS, DNS2) != 0) {return false;} else {mEthManager.setEthernetEnabled(false);Inet4Address inetAddr = getIPv4Address(IP);int prefixLength = maskStr2InetMask(Mask);InetAddress gatewayAddr = getIPv4Address(Gateway);InetAddress dnsAddr = getIPv4Address(DNS);if (inetAddr.getAddress().toString().isEmpty() || prefixLength == 0 || gatewayAddr.toString().isEmpty()|| dnsAddr.toString().isEmpty()) {return false;}ArrayList<InetAddress> dnsServers = new ArrayList<>();dnsServers.add(dnsAddr);if (!DNS2.isEmpty()) {dnsServers.add(getIPv4Address(DNS2));}final StaticIpConfiguration.Builder staticIPBuilder = new StaticIpConfiguration.Builder().setDnsServers(dnsServers).setDomains(mStaticIpConfiguration.getDomains()).setGateway(gatewayAddr).setIpAddress(new LinkAddress(inetAddr, prefixLength));mStaticIpConfiguration = staticIPBuilder.build();IpConfiguration ipConfiguration = new IpConfiguration();ipConfiguration.setIpAssignment(IpConfiguration.IpAssignment.STATIC);ipConfiguration.setProxySettings(IpConfiguration.ProxySettings.NONE);ipConfiguration.setStaticIpConfiguration(mStaticIpConfiguration);mEthManager.setConfiguration(Interface, ipConfiguration);mEthManager.setEthernetEnabled(true);return true;}} else {return false;}}return false;}private Inet4Address getIPv4Address(String text) {try {return (Inet4Address) InetAddresses.parseNumericAddress(text);} catch (IllegalArgumentException | ClassCastException e) {return null;}}public int maskStr2InetMask(String maskStr) {StringBuffer sb;String str;int inetmask = 0;int count = 0;/** check the subMask format*/Pattern pattern = Pattern.compile("(^((\\d|[01]?\\d\\d|2[0-4]\\d|25[0-5])\\.){3}(\\d|[01]?\\d\\d|2[0-4]\\d|25[0-5])$)|^(\\d|[1-2]\\d|3[0-2])$");if (pattern.matcher(maskStr).matches() == false) {Log.e(TAG, "subMask is error");return 0;}String[] ipSegment = maskStr.split("\\.");for (int n = 0; n < ipSegment.length; n++) {sb = new StringBuffer(Integer.toBinaryString(Integer.parseInt(ipSegment[n])));str = sb.reverse().toString();count = 0;for (int i = 0; i < str.length(); i++) {i = str.indexOf("1", i);if (i == -1)break;count++;}inetmask += count;}return inetmask;}private boolean isIpAddress(String value) {int start = 0;int end = value.indexOf('.');int numBlocks = 0;while (start < value.length()) {if (end == -1) {end = value.length();}try {int block = Integer.parseInt(value.substring(start, end));if ((block > 255) || (block < 0)) {return false;}} catch (NumberFormatException e) {return false;}numBlocks++;start = end + 1;end = value.indexOf('.', start);}return numBlocks == 4;}private int validateIpConfigFields(StaticIpConfiguration staticIpConfiguration, String ipAddr,String netmask, String gateway, String dns, String dns2) {final StaticIpConfiguration.Builder staticIPBuilder = new StaticIpConfiguration.Builder().setDnsServers(staticIpConfiguration.getDnsServers()).setDomains(staticIpConfiguration.getDomains()).setGateway(staticIpConfiguration.getGateway()).setIpAddress(staticIpConfiguration.getIpAddress());Inet4Address inetAddr = getIPv4Address(ipAddr);if (inetAddr == null) {return 2;}int networkPrefixLength = -1;networkPrefixLength = maskStr2InetMask(netmask);if(networkPrefixLength == 0){return 3;}InetAddress gatewayAddr = getIPv4Address(gateway);if (gatewayAddr == null) {return 4;}staticIPBuilder.setGateway(gatewayAddr);ArrayList<InetAddress> dnsServers = new ArrayList<>();InetAddress dnsAddr = null;dnsAddr = getIPv4Address(dns);if (dnsAddr == null) {return 5;}dnsServers.add(dnsAddr);InetAddress dnsAddr2 = null;dnsAddr2 = getIPv4Address(dns2);if (dnsAddr2 == null) {return 6;}dnsServers.add(dnsAddr2);staticIpConfiguration  = staticIPBuilder.build();return 0;}

每次开机的时候可以在系统应用中接收开机广播。然后调用initEthIp函数，去检测是否已经设置过静态IP，如果设置过了就用一个系统属性保存标志位，下次再开机的时候判断标志位是否再设置静态IP。