String find = searchFor...

Ludzie pragną czasami się rozstawać, żeby móc tęsknić, czekać i cieszyć się z powrotem.

getText();
int j = 0;
// Select from the list if find exists:
for (int i = 0; i < n.length; i++) {
if(find == null)
rs[j++] = n[i];
else if(n[i].indexOf(find) != -1)
rs[j++] = n[i];
}
results.setText("");
if(strip.getState() == true)
for (int i = 0; i < j; i++)
results.append(
StripQualifiers.strip(rs[i]) + "\n");
else // Leave qualifiers on
for (int i = 0; i < j; i++)
results.append(rs[i] + "\n");
}
class StripL implements ItemListener {
public void itemStateChanged(ItemEvent e) {
reDisplay();
}
776
Thinking in Java
www.BruceEckel.com
}
class SearchForL implements TextListener {
public void textValueChanged(TextEvent e) {
reDisplay();
}
}
public static void main(String[] args) {
DisplayMethods applet = new DisplayMethods();
Frame aFrame = new Frame("Display Methods");
aFrame.addWindowListener(
new WindowAdapter() {
public void windowClosing(WindowEvent e) {
System.exit(0);
}
});
aFrame.add(applet, BorderLayout.CENTER);
aFrame.setSize(500,750);
applet.init();
applet.start();
aFrame.setVisible(true);
}
}
class StripQualifiers {
private StreamTokenizer st;
public StripQualifiers(String qualified) {
st = new StreamTokenizer(
new StringReader(qualified));
st.ordinaryChar(' ');
}
public String getNext() {
String s = null;
try {
if(st.nextToken() !=
StreamTokenizer.TT_EOF) {
switch(st.ttype) {
case StreamTokenizer.TT_EOL:
s = null;
break;
case StreamTokenizer.TT_NUMBER:
s = Double.toString(st.nval);
break;
case StreamTokenizer.TT_WORD:
s = new String(st.sval);
break;
default: // single character in ttype
s = String.valueOf((char)st.ttype);
}
}
} catch(IOException e) {
System.out.println(e);
}
return s;
}
Chapter 17: Projects 777 public static String strip(String qualified) {
StripQualifiers sq =
new StripQualifiers(qualified);
String s = "", si;
while((si = sq.getNext()) != null) {
int lastDot = si.lastIndexOf('.');
if(lastDot != -1)
si = si.substring(lastDot + 1);
s += si;
}
return s;
}
} ///:~
Some things you’ve seen before. As with many of the GUI programs in this book, this is created to perform both as an application and as an applet. Also, the StripQualifiers class is exactly the same as it was in Chapter 11.
The GUI contains a TextField name in which you can enter the fully-qualified class name you want to look up, and another one, searchFor, in which you can enter the optional text to search for within the list of methods. The Checkbox allows you to say whether you want to use the fully-qualified names in the output or if you want the qualification stripped off.
Finally, the results are displayed in a TextArea.
You’ll notice that there are no buttons or other components by which to indicate that you want the search to start. That’s because both of the TextFields and the Checkbox are monitored by their listener objects. Whenever you make a change, the list is immediately updated. If you change the text within the name field, the new text is captured in class NameL. If the text isn’t empty, it is used inside Class.forName( ) to try to look up the class.
As you’re typing, of course, the name will be incomplete and Class.forName( ) will fail, which means that it throws an exception. This is trapped and the TextArea is set to “No match”. But as soon as you type in a correct name (capitalization counts), Class.forName( ) is successful and getMethods( ) and getConstructors( ) will return arrays of Method and Constructor objects, respectively. Each of the objects in these arrays is turned into a String via toString( ) (this produces the complete method or constructor signature) and both lists are combined into n, a single String array. The array n is a member of class DisplayMethods and is used in updating the display whenever reDisplay( ) is called.
If you change the Checkbox or searchFor components, their listeners simply call reDisplay( ). reDisplay( ) creates a temporary array of String called rs (for “result set”).
The result set is either copied directly from n if there is no find word, or conditionally copied from the Strings in n that contain the find word. Finally, the strip Checkbox is interrogated to see if the user wants the names to be stripped (the default is “yes”). If so, StripQualifiers.strip( ) does the job; if not, the list is simply displayed.
In init( ), you might think that there’s a lot of busy work involved in setting up the layout.
In fact, it is possible to lay out the components with less work, but the advantage of using BorderLayouts this way is that it allows the user to resize the window and make – in particular – the TextArea larger, which means you can resize to allow you to see longer names without scrolling.