android真机访问本地局域网tomcat服务器

链接方式：

1）将应用后台服务器部署到某台可以通过公网访问的服务器上，手机访问该公网IP地址，类似于公网试用

（2）设置局域网，手机通过WIFI访问局域网中的某台服务器（拥有局域网IP地址）选择这种方案

下面主要讲android这边的开发

页面部分的按钮触发事件处理逻辑

/**
* 按钮触发下载
*
* @param view
* @throws MalformedURLException
*/
public void startDownImage(View view) throws MalformedURLException {
String path = urlEditText.getText().toString();// 获取图片路径字符串
Toast.makeText(getApplicationContext(), "开始下载图片", Toast.LENGTH_LONG)
.show();
Toast.makeText(
getApplicationContext(),
"IP: " + this.getLocalIpAddress() + "    MAC: "
+ this.getLocalMacAddress(), Toast.LENGTH_LONG).show();
Log.i(TAG, "IP: " + this.getLocalIpAddress());
Log.i(TAG, "MAC: " + this.getLocalMacAddress());
// 下载图片，新建一个异步任务下载图片
ImageService.getImage(showImage, path);

}

/**
* 获取Android本机IP地址
*
* @return
*/
private String getLocalIpAddress() {
try {
for (Enumeration<NetworkInterface> en = NetworkInterface
.getNetworkInterfaces(); en.hasMoreElements();) {
NetworkInterface intf = en.nextElement();
for (Enumeration<InetAddress> enumIpAddr = intf
.getInetAddresses(); enumIpAddr.hasMoreElements();) {
InetAddress inetAddress = enumIpAddr.nextElement();
if (!inetAddress.isLoopbackAddress()) {
return inetAddress.getHostAddress().toString();
}
}
}
} catch (SocketException ex) {
Log.e("WifiPreference IpAddress", ex.toString());
}
return null;
}

/**
* 获取Android本机MAC
*
* @return
*/
private String getLocalMacAddress() {
WifiManager wifi = (WifiManager) this.getApplicationContext()
.getSystemService(Context.WIFI_SERVICE);
WifiInfo info = wifi.getConnectionInfo();

return info.getMacAddress();
}

图片下载服务类

package com.vincent.org.networkapp.download;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.util.Log;
import android.widget.ImageView;

public class ImageService {

private static final String TAG = "ImageService";

private final Context mContext;
private final ImageView mImageView;

public ImageService(Context context, ImageView imageView) {
this.mContext = context;
this.mImageView = imageView;
}

public static Bitmap getImage(ImageView imageView, String pathUrl)
throws MalformedURLException {

// 构建url
URL url = new URL(pathUrl);
// 打开一个http链接
Log.i(TAG, "和服务器开始链接");
DownTask downTaskCase = new DownTask(null, imageView);
downTaskCase.execute(url);
return null;
}

/**
* 异步任务下载网络图片数据 必须对网络请求在新建线程中进行，不能在main线程中进行网络请求这些 时间比较多的请求。不然就报这些NetworkOnMainThreadException异常。 这个错误是说你在main线程里面执行网络操作。最新sdk版本是不允许的。(为了避免anr异常出现)。
所以，解决的话，只要另外开个线程，把网络操作放到新线程里面就好啦
*
* @author cindy
*
*/
private static class DownTask extends AsyncTask<URL, Integer, Bitmap> {
private static final String TAG_DT = "DownTask";
private final Context mContext;
private final ImageView mImageView;

public DownTask(Context context, ImageView imageView) {
this.mImageView = imageView;
this.mContext = context;
}

@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
Log.i(TAG_DT, TAG_DT + "Ready");
}

@Override
protected Bitmap doInBackground(URL... params) {
// TODO Auto-generated method stub
Log.i(TAG_DT, TAG_DT + "begin");
HttpURLConnection urlConnection;
try {
urlConnection = (HttpURLConnection) params[0].openConnection();
urlConnection.setConnectTimeout(500);// 超时时间
urlConnection.setRequestMethod("GET");// 请求方法
if (urlConnection.getResponseCode() == 200) {
Log.i(TAG_DT, "和服务器建立了链接");
// 获得了http的正确响应码后，返回一个输入流
InputStream ins = urlConnection.getInputStream();
Bitmap bitmap = BitmapFactory.decodeStream(ins);
return bitmap;
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

return null;
}

@Override
protected void onPostExecute(Bitmap result) {
// TODO Auto-generated method stub
Log.i(TAG_DT, TAG_DT + "complete");
super.onPostExecute(result);
// 把图像更新到ui
mImageView.setImageBitmap(result);
}

}
}

布局文件

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.vincent.org.networkapp.DownLoadImageShowActivity" >

<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/path"
android:id="@+id/path"/>
<!-- 将下载资源链接直接写进来-->
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="http://192.168.44.119:8080/ServierWebForSimple/vincent.png"
android:id="@+id/pathEditText"
android:layout_below="@id/path" />

<Button
android:id="@+id/startDownImage"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/pathEditText"
android:layout_below="@+id/pathEditText"
android:layout_marginTop="18dp"
android:text="@string/startDownImage"
android:onClick="startDownImage"/>

<ImageView
android:id="@+id/show"
android:layout_width="match_parent"
android:layout_height="match_parent"

android:layout_below="@+id/startDownImage" />

</RelativeLayout>

增加网络访问权限

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>