crawler.HTTPRequest.java Source code

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Here is the source code for crawler.HTTPRequest.java

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/*
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 */

package crawler;

/**
 *
 * @author anna
 */

import java.net.URL;
import java.util.Map;
import java.util.Collection;

import com.google.common.collect.Multimap;
import com.google.common.collect.HashMultimap;
import java.lang.StringBuilder;

// HTTPRequest contains the headers and the body of any HTTP Message
// Clients need to instantiate this class, populate its field, and set it in HTTPClient
// in order to make a request 
public class HTTPRequest {

    private URL url; // if users do not specify port, URL default it to 80
    private String requestBody;
    private Multimap<String, String> headers;
    private Map<String, String> cookies; // convenient place to get cookies

    public HTTPRequest(URL url) {

        this.url = url;
        this.headers = HashMultimap.create();
        this.requestBody = "";

    }

    // adding cookies to the header of sending request
    // side-effect: add more pairs in this.headers
    public void addCookies(Map<String, String> cookies) {

        this.cookies = cookies;

        String key = "Cookie";
        StringBuilder builder = new StringBuilder();

        int i = 0;

        for (String cookieKey : cookies.keySet()) {

            builder.append(cookieKey);
            builder.append("=");
            builder.append(cookies.get(cookieKey));

            if (i != cookies.size() - 1) {
                builder.append("; ");
            }

            i++;
        }

        this.headers.put(key, builder.toString());

    }

    // create the entire HTTP 1.0 message from this HTTPRequest
    public String serializeRequest(HTTPClient.HTTPMethod method) {
        // give StringBuilder some initial capacity will save time if the 
        // request is big
        StringBuilder builder = new StringBuilder(112);

        // BUILDING FIRST LINE 
        builder.append(method.value());
        builder.append(" ");
        String path = this.getURL().getPath();
        builder.append(path == "" ? "/" : path);
        builder.append(" ");
        builder.append("HTTP/1.0\r\n");

        // BUILDING HEADERS 
        Multimap<String, String> headers = this.getHeaders();

        for (String key : headers.keySet()) {

            Collection<String> values = headers.get(key);

            for (String value : values) {
                builder.append(key);
                builder.append(":");
                builder.append(value);
                builder.append("\r\n");
            }
        }

        builder.append("\r\n");

        if (method == HTTPClient.HTTPMethod.POST) {
            builder.append(this.getRequestBody());
        }

        return builder.toString();
    }

    public void setURL(URL url) {
        this.url = url;
    }

    public URL getURL() {
        return this.url;
    }

    public void setRequestBody(String requestBody) {
        this.requestBody = requestBody;
    }

    public String getRequestBody() {
        return this.requestBody;
    }

    public void setHeaders(Multimap<String, String> headers) {
        this.headers = headers;
    }

    public Multimap<String, String> getHeaders() {
        return this.headers;
    }

    public Map<String, String> getCookies() {
        return this.cookies;
    }

    @Override
    public String toString() {
        return "REQUEST :" + "\n" + "URL : " + url.toString() + "\n" + "HEADERS: " + "\n" + headers.toString()
                + "\n" + "BODY : " + "\n" + requestBody + "\n";
    }

}