基本上，我需要编写一个csv解析器，该解析器将考虑用户定义的映射。同时没有定义列的顺序，并且用户可以有任意数量的列，但是Application只会考虑映射中匹配的列。
我试图创建一个映射，其中键将是用户cloumn，值将是休眠实体cloumn。
下一步将是查找是否找到条目，如果找到了下一步，则将是查找列的位置。
try {
List<Student> students = new ArrayList<Student>();
String line = "";
fileReader = new BufferedReader(new FileReader(fileName));
line=fileReader.readLine();
String[] headers = line.split(COMMA_DELIMITER);
int columnCounter=0;
for(String a : headers){// parsing the header
String columnName=clientMapping.get(a);//gettting actual column from mapping defined by user
if(columnName !=null){
switch(columnName.toUpperCase()){
case "FNAME":
STUDENT_FNAME=columnCounter;// finding the position of column
break;
case "LNAME":
STUDENT_LNAME=columnCounter;
break;
case "SEX" :
STUDENT_GENDER=columnCounter;
break;
case "ID" :
STUDENT_ID=columnCounter;
break;
case "AGE" :
STUDENT_AGE=columnCounter;
break;
default :
System.out.println("default");
}
}
columnCounter++;
}
//Read the file line by line starting from the second line
while ((line = fileReader.readLine()) != null) {
//Get all tokens available in line
String[] tokens = line.split(COMMA_DELIMITER);
if (tokens.length > 0) {
//Create a new student object and fill his data
Student student = new Student(Long.parseLong( STUDENT_ID == -1 ? null : tokens[STUDENT_ID]),STUDENT_FNAME == -1 ? null: tokens[STUDENT_FNAME], STUDENT_LNAME == -1 ? null : tokens[STUDENT_LNAME], STUDENT_GENDER == -1 ? null:tokens[STUDENT_GENDER],STUDENT_AGE == -1 ? null: Integer.parseInt(tokens[STUDENT_AGE]));
students.add(student);
}
}
它可以正常工作，但这仅适用于学生班，因为它不是通用的。