Question

如何在java读取文件的路径中加入变量

比如我要读取的是从A058502.D51到A058502.D99的文件，如何通过for循环来读取
A058502.Di
为什么读出来的所有数据都是一样的，已经在每次循环前都释放内存了

Answer 1

直接创建File对象的时候，你把你的路径作为一个参数传递进去不就行了么？new File(arg);
然后后续通过你的文件流读取文件。

int groupNum = PropertiesUtil.getIntValue("batch_size");
long startTime = System.currentTimeMillis();
QueryBasicRoadService service = new QueryBasicRoadService();

int countRdLink = service.countRdLink();
System.out.println("RD_LINK count is : " + countRdLink);
int time = countRdLink / groupNum;
int start = 1;
int end = 0;
for (int i = 1; i <= time; i++) {
if (i == time) {
end = countRdLink;
} else {
end = i * groupNum;
}
List<BasicRoadVO> linkList = service.queryRdLinkList(start, end);
System.out.println("total query size : " + linkList.size());
RoadCoordinateConversion conversion = new RoadCoordinateConversion();
conversion.exportRoadCoordinate(linkList);
start = end + 1;
}
System.out.println("total conversion time : "
+ (System.currentTimeMillis() - startTime));

Answer 2

jdk 7以上
Files.lines(Paths.get(first, more));
也可以自己拼
public void readFile(String 路径,String 变量){
try {
File f=new File(路径+变量);
BufferedReader br=new BufferedReader(new FileReader(f) );

} catch (FileNotFoundException e) {
e.printStackTrace();
}
}

Answer 3

String filename = "A058502.D";
for(int i=51;i<100;i++){
File file = new File(filename+i+"");
//处理文件过程，不要忘记释放资源
}

Answer 4

String path="E:\\";
String filename="A058502.D";
String filepath="";
File file;
for(int i=51;i<=99;i++){
filepath=path+filename+i;
file=new File(filepath);
……//读取文件file
}

Answer 5

String path = "c:\\index" + x;
File file = new File(path);