Professional JavaScript For Web Developers

Client-Server Communication
function httpGet(sURL) {
var oURL = new java.net.URL(sURL);
}
//...
Note that when you use LiveConnect, you must furnish the complete name of the class, including the
package, to instantiate a Java object. After the URL is created, you open up an input stream and create a
reader to get the data back. The preferred way to do this is to create an InputStreamReader and then a
BufferedReader based on it:
function httpGet(sURL) {
var oURL = new java.net.URL(sURL);
var oStream = oURL.openStream();
var oReader = new java.io.BufferedReader(new
java.io.InputStreamReader(oStream));
}
//...
With the buffered reader created, all that’s left to do is read the data back from the server. A buffered
reader gets data line-by-line, so you create a variable to build up the response into the full text. This
response text variable (named sResponseText) must start out as an empty string, not null, so that
string concatenation can be used to build the result:
function httpGet(sURL) {
var oURL = new java.net.URL(sURL);
var oStream = oURL.openStream();
var oReader = new java.io.BufferedReader(new
java.io.InputStreamReader(oStream));
var sResponseText = “”;
var sLine = oReader.readLine();
while (sLine != null) {
sResponseText += sLine + “\n”;
sLine = oReader.readLine();
}
}
//...
Because the buffered reader returns lines, each line must be appended with a new line character to
ensure that it remains in the same form, as it should. The last steps are to close the reader and return
the response text:
function httpGet(sURL) {
var oURL = new java.net.URL(sURL);
var oStream = oURL.openStream();
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