字符串转整型问题

Question

       System.out.println(gv.getGclaGrade());                          //这个输出结果是10 int g=0; 
try { 
g = Integer.valueOf(gv.getGclaGrade()).intValue(); 
} catch (NumberFormatException e) { 
System.out.println("格式化失败"); 
System.out.println(g);                                //这里输出的结果却是0 
e.printStackTrace(); 
} 
System.out.println(g); 
格式化我查了好多遍，不知道问题出在哪里，高手指点一下。

Answer 1

java.lang.NumberFormatException: For input string: "10  "
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:48)
at java.lang.Integer.parseInt(Integer.java:456)
at java.lang.Integer.valueOf(Integer.java:553)
at com.xiaoshimaomao.struts.action.GoodClassAddAction.add(GoodClassAddAction.java:42)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:270)
at org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:187)
at org.apache.struts.actions.MappingDispatchAction.execute(MappingDispatchAction.java:169)
at org.springframework.web.struts.DelegatingActionProxy.execute(DelegatingActionProxy.java:106)
at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:269)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:96)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:75)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:215)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:188)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:174)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:117)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:108)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:151)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:874)
at org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:665)
at org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:528)
at org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:81)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:689)
at java.lang.Thread.run(Thread.java:595)
0

Answer 2

gv.getGclaGrade()是不是有个空格啊

Answer 3

10后面有空格吧。。要先trim一下

Answer 4

嗯,同意楼上各位的,很有可能有空格什么的,用trim一下试试

Answer 5

看这里的提示，是10后面还有空格应该在gv.getGclaGrade()加上trim()方法
System.out.println(gv.getGclaGrade().trim());

Answer 6

java.lang.NumberFormatException: For input string: "10  "你的字符串有空格
加一句trim()就可以了。System.out.println(gv.getGclaGrade());                          //这个输出结果是10 int g=0; 
String str;
try { 
str = gv.getGclaGrade();
str.trim();
g = Integer.valueOf(str).intValue(); 

Answer 7

写错了。补充下上面。str = str.trim();

Answer 8

解决了，谢谢！
g = Integer.valueOf(gv.getGclaGrade().trim()).intValue();
不过还是不明白，为什么会出现空格呢？