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Java catch Fildnot发现异常e和一个try方法_Java_Exception_Generics - Fatal编程技术网

Java catch Fildnot发现异常e和一个try方法

Java catch Fildnot发现异常e和一个try方法,java,exception,generics,Java,Exception,Generics,我有这个问题,我不知道编码有什么问题 catch (FilenotFoundException e){ system.out.println("File not found"); } try { FileReader freader = new FileReader("MyFile.txt"); } } 它问的是错误是什么??我想可能是e没有大写,原因是?一个try{}块后面应该跟

我有这个问题,我不知道编码有什么问题

    catch (FilenotFoundException e){
        system.out.println("File not found");

        }
        try
        {
            FileReader freader = new FileReader("MyFile.txt");
        }
}
它问的是错误是什么??我想可能是e没有大写,原因是?

一个try{}块后面应该跟一个catch{}块,或者最后一个{}块,你把它颠倒了

这样使用:-

    try {
        FileReader freader = new FileReader("MyFile.txt");

    } catch (FileNotFoundException e){

        System.out.println("File not found");
    }
根据Java命名约定:-

类名以大写字母开头,所有后续单词也以大写字母开头。因此,FilenotFoundException应该是FilenotFoundException

而且,系统应该是->系统

这应该是另一种方式。试着接住

catch{}块跟随try{}块,而不是相反

此外,FilenotFoundException应该是FilenotFoundException。我怀疑它是否能用另一种拼法编译。正如@Rohit Jain的回答所示,system vs.system也是如此。

自Java 7以来:

try( FileReader freader = new FileReader("MyFile.txt"))
{
使用freader


捕捉块应跟随try

try {
  //code that exception might occur
 }
 catch(Exception ex) {
   //catch the exception here.
  }
try块后面应该跟catch或finally

try {
  //code that exception might occur
 }
 finally {
  //close your resources here
 }
try {
  //code that exception might occur
 }
 catch(Exception ex) {
   //catch the exception here.
  }
try {
  //code that exception might occur
 }
 finally {
  //close your resources here
 }