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不规范的代码如下：

import java.io.BufferedReader;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.util.ArrayList;import java.util.List;public class GetClassError {		public List getClass(String fileName){		File classFile = new File(fileName);		List classNames = new ArrayList();		try{			FileReader fileReader = new FileReader(classFile);			BufferedReader bufferread = new BufferedReader(fileReader);			String readContent = null ;						try{				while((readContent=bufferread.readLine())!=null){					classNames.add(readContent);				}				bufferread.close();				fileReader.close();			}catch(IOException e){				e.printStackTrace();			}				}catch(FileNotFoundException e){			e.printStackTrace();		}				return classNames ;	}		public static void main(String args[]){		GetClassError t = new GetClassError();		List classNames = t.getClass("C:\\Users\\TF\\Desktop\\aaa.txt");		System.out.println(classNames.toString());	}}

package com.sides.hkc;import java.io.BufferedReader;import java.io.File;import java.io.FileNotFoundException;import java.io.FileReader;import java.io.IOException;import java.util.ArrayList;import java.util.List;public class GetClassRight {		public List getClass(String fileName){		File classFile = new File(fileName);		List classNames = new ArrayList();		FileReader fileReader = null;		try{			fileReader = new FileReader(classFile);			BufferedReader bufferread = new BufferedReader(fileReader);			String readContent = null ;						try{				while((readContent=bufferread.readLine())!=null){					classNames.add(readContent);				}//				bufferread.close();//				fileReader.close();			}catch(IOException e){				e.printStackTrace();			}finally{				if(bufferread!=null){					try{						bufferread.close();					}catch (IOException e){						throw new RuntimeException("关闭失败");					}				}							}				}catch(FileNotFoundException e){			e.printStackTrace();		}finally{			if(fileReader!=null){				try{					fileReader.close();				}catch (IOException e){					throw new RuntimeException("关闭失败");				}			}		}				return classNames ;	}		public static void main(String args[]){		GetClassRight t = new GetClassRight();		List classNames = t.getClass("C:\\Users\\TF\\Desktop\\aaa.txt");		System.out.println(classNames.toString());	}}

2.多个流关闭时的异常需要分try进行关闭，参考上一文中的io操作注意一文  

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