我正在尝试从结构化TXT到Excel表创建一个转换器,我遇到了TXT文件读取和正确数据存储的问题。
提供TXT文件,内容如下:
-
HOSTNAME:hostname1
IP:ipAddress1
设备信息:
名称:deviceName1_1,SERIALNUMBER:serialNumber1_1
-
HOSTNAME:hostname2
IP:ipAddress2
设备信息:
名称:deviceName2_1,SERIALNUMBER:serialNumber2_1
名称:deviceName2_2, SERIALNUMBER:serialNumber2_2
名称:deviceName2_3,SERIALNUMBER: serialNumber2_3
-
HOSTNAME:hostname3
IP:ipAddress3
设备信息:
名称:deviceName3_1,SERIALNUMBER:serialNumber3_1
名称:deviceName3_2, SERIALNUMBER:serialNumber3_2
请注意,此TXT文件包含3个信息块。每个信息块由特殊符号" - "分开。 TXT文件可以包含更多或更少的信息块。在设备信息下,可以有更多或更少的设备名称和序列号。
期望解析文件并将数据存储在创建的对象中。
对象应包含以下字段:
String hostname;
String ip;
String name;
String serialnumber;
通常每个信息块可以创建1个对象。如果在设备信息下有多行设备名称和序列号,则应创建具有相同主机名的多个对象和 IP ,但不同的设备名称和序列号。
预期结果:
总共应使用以下数据创建6个对象。
对象#1有hostname1,ipAddress1,deviceName1,serialNumber1
对象#2有hostname2,ipAddress2,deviceName2_1,serialNumber2_1
对象#3有hostname2,ipAddress2,deviceName2_2,serialNumber2_2
对象#4有hostname2,ipAddress2, deviceName2_3,serialNumber2_3
对象#5有 hostname3,ipAddress3,deviceName3_1,serialNumber3_1
对象#6有hostname3,ipAddress3,deviceName3_2,serialNumber3_2
到目前为止,我尝试编写此代码:
private ArrayList<Device> readFile() {
ArrayList<Device> devices = new ArrayList<Device>
BufferedReader br = null;
try {
br = new BufferedReader(new InputStreamReader(new FileInputStream(txtFile)));
String line = "";
String data;
int i=0;
while ((line = br.readLine()) != null) {
// Device device = new Device();
if (line.equals("-")) {
// Device device = new Device();
while ((line = br.readLine()) != null) {
Device device = new Device();
if (line.contains("HOSTNAME: ")) {
// Device device = new Device();
if (line.substring(0,10).equals("HOSTNAME: ")) {
device.setHostname(line.substring(10,line.length()));
devices.add(device);
}
}
if (line.contains("IP: ")) {
// Device device = new Device();
if (line.substring(0,4).equals("IP: ")) {
device.setIp(line.substring(4,line.length()));
devices.add(device);
}
}
devices.add(device);
}
}
}
}
但是对象有一个主机名,但IP是NULL,反之亦然。我也试过这段代码:
try {
Scanner scanner = new Scanner(txtFile);
int i = 0;
while (scanner.hasNextLine()) {
String line = scanner.nextLine();
String array[] = line.split(",");
DeviceData device = new DeviceData(array[0],array[1]);
System.out.println("Eilute " + (i++) + ": " + array[0]);
}
但我在这里迷失了自己。
我在分离所需数据并将其放入对象时遇到问题。我应该如何按预期做到这一点?有什么想法和/或建议吗?
答案 0 :(得分:1)
当遇到以“NAME:”开头的行时,您应该创建设备对象。为了保留IP和HOSTNAME值,您应该使用局部变量。示例实现可能如下所示:
br = new BufferedReader(new InputStreamReader(
new FileInputStream(txtFile)));
String line;
while ((line = br.readLine()) != null) {
if (line.equals("-")) {
String ip = null;
String hostname = null;
while ((line = br.readLine()) != null) {
if (line.contains("HOSTNAME: ")) {
if (line.substring(0, 10).equals("HOSTNAME: ")) {
hostname = line.substring(10, line.length());
}
}
if (line.contains("IP: ")) {
if (line.substring(0, 4).equals("IP: ")) {
ip = line.substring(4, line.length());
}
}
if (line.contains("NAME: ")) {
if (line.substring(0, 6).equals("NAME: ")) {
Device device = new Device();
device.setIp(ip);
device.setHostname(hostname);
System.out.println("Adding device with ip = " +
ip + " and hostname " + hostname);
System.out.println("Details: " + line);
devices.add(device);
}
}
}
}
}
答案 1 :(得分:0)
我会将解析结构化为多个函数,并检查文件的语法是否正确。建议:
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
public class ReadDevices {
public static class InvalidFileException extends Exception {
private static final long serialVersionUID = -6525977749423883875L;
}
public static void main(String[] args) {
ArrayList<Device> devices;
try {
devices = readFile("yourFile.txt");
} catch (IOException | InvalidFileException e) {
System.out.println("Something is wrong with the file!");
return;
}
// do something with devices
}
public static ArrayList<Device> readFile(String file) throws IOException, InvalidFileException {
ArrayList<Device> devices = new ArrayList<Device>();
BufferedReader reader = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
// discard "-"
assertLine(reader.readLine(), "-");
String hostnameLine;
while ((hostnameLine = reader.readLine()) != null) {
String hostname = parseLineWithLabel(hostnameLine, "HOSTNAME");
String ip = parseLineWithLabel(reader.readLine(), "IP");
assertLine(reader.readLine(), "DEVICE INFO:");
String line;
String[] deviceLabels = new String[] { "NAME", "SERIALNUMBER" };
while ((line = reader.readLine()) != null) {
if (line.equals("-"))
break;
String[] deviceInfo = parseLineWithMultiLabel(line, deviceLabels);
devices.add(new Device(hostname, ip, deviceInfo[0], deviceInfo[1]));
}
}
reader.close();
return devices;
}
private static String parseLineWithLabel(String line, String label) throws InvalidFileException {
String[] parts = line.split(": ");
if (!parts[0].equals(label))
throw new InvalidFileException();
return parts[1];
}
private static String[] parseLineWithMultiLabel(String line, String[] labels) throws InvalidFileException {
String[] multi = line.split(", ");
String[] result = new String[multi.length];
for (int i = 0; i < multi.length; i++)
result[i] = parseLineWithLabel(multi[i], labels[i]);
return result;
}
private static void assertLine(String line, String value) throws InvalidFileException {
if (!line.equals(value))
throw new InvalidFileException();
}
}
如果文件没有正确的结构,它将抛出InvalidFileException。然后,您可以在调用函数中处理错误。