我是RESTful Webservices中的新手，并尝试从Client调用double [] []值数组。我可以使用XMLpullparser检索单行数组。我需要将整个数组调用到客户端。请帮忙。 Im gona发布了REST Web服务代码和客户端代码。
REST Webservices -
（资源类）
import java.util.List;
import javax.jws.WebService;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import org.mushtaq.javabrains.matrix.model.MatrixModel;
import org.mushtaq.javabrains.matrix.service.MatrixService;
@Path("/MatrixResource")
@WebService
public class MatrixResource {
double [][] a,b;
MatrixService ms = new MatrixService();
@GET
@Produces(MediaType.APPLICATION_XML)
public List<MatrixModel> RandomArraynew (){
a= ms.RandomArray(100);
b= ms.RandomArray1(100);
return ms.Multi(a,b);
}
}
（服务类）
package org.mushtaq.javabrains.matrix.service;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;
import org.mushtaq.javabrains.matrix.model.MatrixModel;
import org.mushtaq.javabrains.matrix.resource.MatrixResource;
public class MatrixService {
public double[][] RandomArray(int n) {
double[][] randomMatrix = new double[n][n];
double[] randomArray = new double[n];
Random rand = new Random();
rand.setSeed(System.currentTimeMillis());
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
Integer r = rand.nextInt() % 100;
randomMatrix[i][j] = Math.abs(r);
}
}
return randomMatrix;
}
public double[][] RandomArray1(int n) {
double[][] randomMatrix1 = new double[n][n];
double[] randomArray = new double[n];
Random rand = new Random();
rand.setSeed(System.currentTimeMillis());
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
Integer r = rand.nextInt() % 100;
randomMatrix1[i][j] = Math.abs(r);
}
}
return randomMatrix1;
}
public List<MatrixModel> Multi(double a [][], double b[][]){
if(a.length == 0) return new double [0][0];
if(a[0].length != b.length) return null; //invalid dims
int q = a[0].length;
int m = a.length;
int p = b[0].length;
double ans[][] = new double[m][p];
for(int i = 0;i < m;i++){
for(int j = 0;j < p;j++){
for(int k = 0;k < q;k++){
ans[i][j] += a[i][k] * b[k][j];
}
}
}
MatrixModel r= new MatrixModel(ans);
ArrayList<MatrixModel> list = new ArrayList<>();
list.add(r);
return list;
}
}
package org.mushtaq.javabrains.matrix.model;
import javax.xml.bind.annotation.XmlRootElement;
@XmlRootElement
public class MatrixModel {
double [][] result;
public MatrixModel(){
}
public MatrixModel(double [][] result){
this.result=result;
}
public double[][] getResult() {
return result;
}
public void setResult(double[][] result) {
this.result = result;
}
}
以上三个是RESTWebservice类，它应该向Client返回一个double [] []值数组。我可以通过URL =＆＃34;在浏览器中完美地调用它。 http://172.21.202.7:8080/matrix/webapi/MatrixResource＆＃34 ;.它以XML格式显示数组。我被卡住了，如何从客户端调用这整个数组。当我调用服务时，它只显示一行数组。我的客户端代码如下所示。
客户代码 -
（MyActivityClass）
package com.example.Comp_Offloading;
import android.app.ActionBar;
import android.app.Activity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
import java.io.IOException;
import java.util.List;
public class MyActivity extends Activity {
TextView txt;
TextView txt2;
TextView txt3;
EditText etxt, etxt2;
Button bt, bt2;
TextView output;
ProgressBar pb;
ActionBar ab;
List<Matrix> matlist;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
txt = (TextView) findViewById(R.id.textView);
txt2 = (TextView) findViewById(R.id.textView2);
txt3=(TextView)findViewById(R.id.textView3);
etxt=(EditText)findViewById(R.id.editText);
etxt2=(EditText)findViewById(R.id.editText2);
bt = (Button) findViewById(R.id.button);
bt2 = (Button) findViewById(R.id.button2);
//i = (ImageButton) findViewById(R.id.imageButton);
bt2.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view){
etxt.setText("");
etxt2.setText("");
txt.setText("");
etxt.requestFocus();
}
});
bt.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (isOnline())
{requestData("http://172.21.202.7:8080/matrix/webapi
/MatrixResource");
}
}
});}
private void requestData(String Uri) {
MyTask task= new MyTask();
task.execute(Uri);
}
protected void updateDisplay() {
if (matlist != null) {
for (Matrix matrix : matlist) {
txt.append(matrix.getResult() + "");
}
}
}
protected boolean isOnline(){
ConnectivityManager cm= (ConnectivityManager)
getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo netinfo=cm.getActiveNetworkInfo();
if (netinfo != null && netinfo.isConnectedOrConnecting()) {
return true;
}
else{
Toast.makeText(this, "Network is not available",
Toast.LENGTH_LONG).show();
return false;}
}
private class MyTask extends AsyncTask<String,String,String> {
@Override
protected void onPreExecute() {
//updateDisplay("Starting Task...");
//pb.setVisibility(View.VISIBLE);
}
@Override
protected String doInBackground(String... params) {
String content = null;
try {
content = HttpManager.getData(params[0]);
} catch (IOException e) {
e.printStackTrace();
}
return content;
}
protected void onPostExecute(String result) {
matlist = MatrixXMLParser.parseFeed(result);
updateDisplay();
//pb.setVisibility(View.INVISIBLE);
}
}
}
（HTTPManager类）
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class HttpManager {
public static String getData(String Uri) throws IOException {
BufferedReader reader = null;
try {
URL url = new URL(Uri);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
StringBuilder sb = new StringBuilder();
reader= new BufferedReader(new InputStreamReader(con.getInputStream()));
String line;
while((line= reader.readLine()) !=null){
sb.append(line + "\n");
}
return sb.toString();
}catch(Exception e){
e.printStackTrace();
return null;
}finally {
if(reader !=null){
reader.close();
}
}
}
}
***(XMLPullparser Class)***
package com.example.Comp_Offloading;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserFactory;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class MatrixXMLParser {
public static List<Matrix> parseFeed(String content) {
try {
boolean inDataItemTag = false;
String currenTagName = "";
Matrix matrix = null;
List<Matrix> matlist = new ArrayList<>();
XmlPullParserFactory factory = XmlPullParserFactory.newInstance();
XmlPullParser parser = factory.newPullParser();
parser.setInput(new StringReader(content));
int everntType = parser.getEventType();
while (everntType != XmlPullParser.END_DOCUMENT) {
switch (everntType) {
case XmlPullParser.START_TAG:
currenTagName = parser.getName();
if (currenTagName.equals("result")) {
inDataItemTag = true;
matrix = new Matrix();
matlist.add(matrix);
}
break;
case XmlPullParser.END_TAG:
if (parser.getName().equals("result")) {
inDataItemTag = false;
}
currenTagName = "";
break;
case XmlPullParser.TEXT:
if (inDataItemTag && matrix != null) {
switch (currenTagName) {
case "item":matrix.setResult(Double.parseDouble(parser.getText()));
break;
default:
break;
}
}
break;
}
everntType = parser.next();
}
return matlist;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
***(Model Class)***
package com.example.Comp_Offloading;
public class Matrix {
private double item;
public double getResult() {
return item;
}
public void setResult(double result) {
this.item = result;
}
}
请帮忙。检查并建议客户端代码中的错误。我应该添加什么来调用整个数组并在客户端显示。还建议，如果除了XMLpullparser之外还有其他任何简单的方法将整个数组显示为纯文本。谢谢
答案 0 :(得分：0)
HTTP响应不支持纯文本响应中的数组。 您需要手动将数组表示为String，将返回类型更改为String并返回如下：
return Arrays.toString(arr);
或者您可以将数组转换为List：return Arrays.asList（arr）;