正则表达式问题

Question

可能是Pattern pat = Pattern.compile(std,Pattern.COMMENTS);//此处报错，但我觉得没错 
这里的std描述的正则表达式不正确，从而不能正确创建Pattern对象，所以出错
希望能帖出异常。

Answer 1

这些是抛出的异常。多谢各位java.util.regex.PatternSyntaxException: Illegal repetition near index 21
public class JavaTest {
                     ^
at java.util.regex.Pattern.error(Unknown Source)
at java.util.regex.Pattern.closure(Unknown Source)
at java.util.regex.Pattern.sequence(Unknown Source)
at java.util.regex.Pattern.expr(Unknown Source)
at java.util.regex.Pattern.compile(Unknown Source)
at java.util.regex.Pattern.<init>(Unknown Source)
at java.util.regex.Pattern.compile(Unknown Source)
at graDesign.Exam.codeMatch(Exam.java:101)
at graDesign.Exam.checkCode(Exam.java:144)
at graDesign.Exam.Get(Exam.java:215)
at graDesign.Exam.Save(Exam.java:276)
at graDesign.Exam$2.mouseClicked(Exam.java:526)
at java.awt.AWTEventMulticaster.mouseClicked(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)

Answer 2

Pattern p = Pattern.compile("a*b",Pattern.COMMENTS);
 Matcher m = p.matcher("aaaaab");
 boolean b = m.matches();
 System.out.println(b);我这么写没有问题,看样子应该是传的参数问题,你加个断点跟踪一下.

Answer 3

 Pattern pat = Pattern.compile(std,Pattern.COMMENTS);//此处报错，但我觉得没错 std加上引号...

Answer 4

你的std 里有特殊字符吧，建议把std打出来看看，有些字符需要处理一下