android 正则

class SearchWather implements TextWatcher{


//监听改变的文本框 
private EditText editText; 

/**
* 构造函数
*/ 
public SearchWather(EditText editText){ 
this.editText = editText; 
} 

@Override 
public void onTextChanged(CharSequence ss, int start, int before, int count) { 
String editable = editText.getText().toString(); 
String str = stringFilter(editable.toString());
if(!editable.equals(str)){
editText.setText(str);
//设置新的光标所在位置 
editText.setSelection(str.length());
}
} 

@Override 
public void afterTextChanged(Editable s) { 

} 
@Override 
public void beforeTextChanged(CharSequence s, int start, int count,int after) { 

} 

} 


public static String stringFilter(String str)throws PatternSyntaxException{    
// 只允许字母和数字      
String   regEx  =  "[^a-zA-Z0-9]";                    
Pattern   p   =   Pattern.compile(regEx);    
Matcher   m   =   p.matcher(str);    
return   m.replaceAll("").trim();    
}