移动开发中的通信架构(四)

这篇文章讲解真正的网络请求类HttpClient&＃xff0c;它负责打开网络链接&＃xff0c;获取数据&＃xff0c;把数据存放于一个字节数组&＃xff0c;让Response解析。

以下是代码&＃xff1a;

package app.http; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import javax.microedition.io.Connector; import javax.microedition.io.HttpConnection; import app.program.GameConst; /** * 功能&＃xff1a; * * 打开网络链接&＃xff0c;获取数据&＃xff0c;把数据存放于一个字节数组&＃xff0c;让Response解析 */ public class HttpClient { // 注: HttpsConnection继承自HttpConnection private HttpConnection conn &＃61; null; private InputStream inputStream &＃61; null; private OutputStream outputStream &＃61; null; private Request request &＃61; null; int msgId; public HttpClient(int _msgId) { msgId &＃61; _msgId; } public Response getResponse(Request request) throws Exception { if (request &＃61;&＃61; null) { return null; } try { this.request &＃61; request; Response resp &＃61; new Response(); // 打开链接 makeConnection(); // 设置参数 setProperty(); // 写入内容 setContent(); // 打开输入流 makeInputStream(); // 得到响应码 resp.responseCode &＃61; conn.getResponseCode(); if (resp.responseCode !&＃61; HttpConnection.HTTP_OK) { return null; } String strContentLength &＃61; conn.getHeaderField("content-length"); if (strContentLength !&＃61; null) { resp.contentLength &＃61; Integer.parseInt(strContentLength); } resp.analysisData(readResponse(), true); return resp; } catch (Exception e) { e.printStackTrace(); throw e; } finally { this.request &＃61; null; cleanup(); } } private void makeConnection() throws Exception { conn &＃61; (HttpConnection) Connector.open("http://", Connector.READ_WRITE, true); } private void makeInputStream() throws Exception { inputStream &＃61; conn.openInputStream(); } private void makeOutputStream() throws Exception { outputStream &＃61; conn.openOutputStream(); } /** * 参数设置 * * &＃64;throws Exception */ private void setProperty() throws Exception { conn.setRequestMethod(HttpConnection.POST); } public void setContent() throws Exception { if (request.getContent() !&＃61; null) { conn.setRequestProperty("Content-Length", String.valueOf(request.getContent().length)); makeOutputStream(); outputStream.write(request.getContent()); } } /** * 从网络流中读取数据&＃xff0c;存放于字节数组中 * * &＃64;return * &＃64;throws Exception */ private byte[] readResponse() throws Exception { try { byte[] data &＃61; null; if (conn !&＃61; null && inputStream !&＃61; null) { int len &＃61; (int) conn.getLength(); // 读取模式1&＃xff1a;直接获取数据长度 if (conn.getRequestMethod().equals(HttpConnection.HEAD)) { return null; } if (len <&＃61; 0) { // 读取模式2&＃xff1a;从Http连接头获取数据长度 String bodyLength &＃61; null; try { bodyLength &＃61; conn.getHeaderField("content-length"); } catch (IOException e) { e.printStackTrace(); } if (bodyLength !&＃61; null) { try { len &＃61; Integer.parseInt(conn.getHeaderField("Body-Length")); } catch (Exception e) { e.printStackTrace(); } } } if (len > 0) { int actual &＃61; 0; int bytesread &＃61; 0; data &＃61; new byte[len]; while ((bytesread !&＃61; len) && (actual !&＃61; -1)) { actual &＃61; inputStream.read(data, bytesread, len - bytesread); if (actual >&＃61; 0) { bytesread &＃43;&＃61; actual; } } if (bytesread &＃61;&＃61; 0) { return null; } else if (bytesread
重点关注方法是&＃xff1a;

public Response getResponse(Request request) throws Exception&＃xff1b;

代码里面涉及了Response和StructResponse&＃xff0c;它们的代码页一并罗列&＃xff1a;

package app.http; import java.io.ByteArrayInputStream; import java.io.DataInputStream; import java.io.EOFException; import java.io.IOException; import java.util.Hashtable; import java.util.Vector; import app.program.Globe; /** * 返回信息的解析方法类&＃xff0c;和StructRequest对应 */ public class StructResponse { private DataInputStream in; private ByteArrayInputStream bin; private Hashtable hash; private Vector vec; private int size; public StructResponse(byte[] data) { bin &＃61; new ByteArrayInputStream(data); in &＃61; new DataInputStream(bin); } public StructResponse(byte[] data, boolean bTradeCipher) { hash &＃61; new Hashtable(); vec &＃61; new Vector(); if (!bTradeCipher) { readTradeData(data); } else { readTradeCipherData(data); } this.getTable(); } private boolean bTable &＃61; false; private int tableIndex &＃61; 0; // 表格数据的列数 private void readTradeData(byte[] data) { int i &＃61; 0; try { for (; i 0) { String s &＃61; new String(data, 0, i, "UTF-8"); putInHash(s); } break; } else if (data[i] &＃61;&＃61; 0x04) { bTable &＃61; false; String s &＃61; new String(data, 0, i, "UTF-8"); vec.addElement(s); if (tableIndex &＃61;&＃61; 0) { tableIndex &＃61; vec.size(); } break; } } String s &＃61; new String(data, 0, i, "UTF-8"); putInHash(s); } catch (Exception ex) { ex.printStackTrace(); } if (data.length - i - 1 > 0) { byte[] nData &＃61; new byte[data.length - i - 1]; System.arraycopy(data, i &＃43; 1, nData, 0, data.length - i - 1); readTradeData(nData); } } private void readTradeCipherData(byte[] data) { for (int i &＃61; 0; i &＃61; 0) { String s1 &＃61; s.substring(0, index); String s2 &＃61; s.substring(index &＃43; 1, s.length()); this.hash.put(s1, s2); } } public String getHashData(String key) { return (String) hash.get(key); } public String[][] getTable() { if (tableIndex <&＃61; 0) { return null; } int line &＃61; vec.size() / this.tableIndex; String[][] tmp &＃61; new String[line][tableIndex]; for (int i &＃61; 0; i

package app.http; import java.util.Hashtable; import java.io.*; /** * 按照私有协议&＃xff0c;解析数据&＃xff0c;和Request对应&＃xff0c;把最终解析结果存放于一个hash中&＃xff0c;存放格式是 消息码--消息内容 */ public class Response { private Hashtable hash &＃61; new Hashtable(); public int responseCode; public int contentLength; private static final byte START_FLAG &＃61; (byte) &＃39;{&＃39;; private static final byte END_FLAG &＃61; (byte) &＃39;}&＃39;; private static final byte OTHER_FLAG &＃61; (byte) &＃39;:&＃39;; public Response() { } /** * 分析数据 解析TYPE和真正数据content * * &＃64;param data * byte[] */ public void analysisData(byte[] _data, boolean isStart) { StructResponse struct &＃61; new StructResponse(_data); byte[] data &＃61; null; try { while (isStart) { int v &＃61; struct.readByte(); if (v &＃61;&＃61; -1) { throw new IOException(" DATA"); } if (v &＃61;&＃61; START_FLAG) { break; } } int type &＃61; struct.readShort(); struct.readByte(); // 0 标志位 struct.readByte(); // 0 标志位 data &＃61; struct.readByteArray(); byte tmp &＃61; (byte) struct.readByte(); if (tmp &＃61;&＃61; END_FLAG) { hash.put(Integer.toString(type), data); } else if (tmp &＃61;&＃61; OTHER_FLAG) { hash.put(Integer.toString(type), data); analysisData(struct.getOthers(), false); } else { throw new IOException("BAD DATA"); } } catch (IOException ex) { ex.printStackTrace(); } } public int getResponseCode() { return responseCode; } public int getContentLength() { return contentLength; } public byte[] getData(int key) { return (byte[]) hash.get(Integer.toString(key)); } public int getResponseNum() { return hash.size(); } }