【发布时间】：2012-04-27 08:36:52
【问题描述】：
我正在 Android 中测试 tuProlog。我有一个活动 TuProlog，类 Parser 与序言代码和 data.pl 交互，其中包含序言代码。我可以将它作为一个输出到控制台的 java 项目很好地运行，但作为一个 Android 项目我遇到了麻烦。对于 Android，即使我的文件 data.pl 被复制到项目的根目录、src 和我的包中，我也会得到 FileNotFoundException。我只想将结果作为字符串获取并在 TextView 中显示我的结果。这是我的代码
public class TuProlog extends Activity implements OnClickListener{
TextView tv;
Button b1;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv = (TextView)findViewById(R.id.label);
b1 = (Button)findViewById(R.id.button1);
b1.setOnClickListener(this);
}
@Override
public void onClick(View v) {
Parser custom = new Parser();
String result = custom.parse();
tv.setText(result);
}
}
public class Parser {
Prolog engine;
PrintStream orgStream = System.out;
ByteArrayOutputStream baos = new ByteArrayOutputStream();
PrintStream psout = new PrintStream(baos, Boolean.TRUE); // Using autoFlush
String myResult ;
public String parse()
{
engine = new Prolog();
try{
Theory t = new Theory(new FileInputStream("data.pl"));
try{
engine.setTheory(t);
try{
SolveInfo answer = engine.solve("likes(john,X).");
try{
Term derivative = answer.getTerm("X");
return myResult;;
}
catch (NoSolutionException e){
e.printStackTrace();
}
catch (UnknownVarException e){
e.printStackTrace();
}
}
catch (MalformedGoalException e){
e.printStackTrace();
}
}
catch (InvalidTheoryException e){
e.printStackTrace();
}
}
catch (FileNotFoundException e){
e.printStackTrace();
}
catch (IOException e){
e.printStackTrace();
}
return null;
}
@Override
public void onSpy(SpyEvent e) {
// TODO Auto-generated method stub
Log.d("TAG", "** LG'd onSpy => SpyEvent Occured ** " );
System.out.println("** onSpy => SpyEvent Occured ** \n ");
myResult = e.getMsg();
}
@Override
public void onOutput(OutputEvent e) {
// TODO Auto-generated method stub
Log.d("TAG", "** LG'd: onOutput => OutputEvent Occured ** " );
System.out.println("** onOutput => OutputEvent Occured ** \n ");
myResult = e.getMsg();
}
@Override
public void onWarning(WarningEvent e) {
// TODO Auto-generated method stub
Log.d("TAG", "** LG'd: onWarning => WarningEvent Occured ** " );
System.out.println("** onWarning => WarningEvent Occured ** \n ");
myResult = e.getMsg();
}
}
数据.pl
likes(john,mary).
likes(mary,wine).
这是我的 logcat 输出，我不知道 System.err
04-15 18:51:25.480: W/System.err(23813): java.io.FileNotFoundException: /data.pl (No such file or directory)
04-15 18:51:25.484: W/System.err(23813): at org.apache.harmony.luni.platform.OSFileSystem.open(Native Method)
04-15 18:51:25.484: W/System.err(23813): at dalvik.system.BlockGuard$WrappedFileSystem.open(BlockGuard.java:232)
04-15 18:51:25.484: W/System.err(23813): at java.io.FileInputStream.<init>(FileInputStream.java:80)
04-15 18:51:25.484: W/System.err(23813): at java.io.FileInputStream.<init>(FileInputStream.java:132)
04-15 18:51:25.484: W/System.err(23813): at com.tuprolog.alicia.Parser.parse(Parser.java:32)
04-15 18:51:25.484: W/System.err(23813): at com.tuprolog.alicia.TuProlog.onClick(TuProlog.java:51)
04-15 18:51:25.484: W/System.err(23813): at android.view.View.performClick(View.java:2485)
04-15 18:51:25.484: W/System.err(23813): at android.view.View$PerformClick.run(View.java:9080)
04-15 18:51:25.484: W/System.err(23813): at android.os.Handler.handleCallback(Handler.java:587)
【问题讨论】：