如何从 java 中的列表中删除子列表，其中特定 substring 作为开始索引，特定 substring 作为结束索引？

Question

Every sublist starts with code 0011 and ends with code 0082. If the end code 0082 has value "W", that sublist should be deleted. Can someone please help, what approach to be taken to delete all the sublists from the list, which are not containing desired value of the end code?

0011 : 4202142599
0012: 031121
0009: CONG TY TNHH MTV THUONG MAI DICH VU AN NHIEN
0006: THON HOACH THON XA DINH TANG HUYEN YEN DINH TINH THANH HOA
1011: VN
0330: 00133
0269: annhien Farm
1021: *AN/NHIEN/FARM&
1021: *AN/NHIEN&
0045: 31
0082 : M
0011 : 4202142599
0012: 031121
0009: CONG TY TNHH MTV THUONG MAI DICH VU AN NHIEN
0006: THON HOACH THON XA DINH TANG HUYEN YEN DINH TINH THANH HOA
1011: VN
0330: 00133
0269: annhien Farm
1021: *AN/NHIEN/FARM&
1021: *AN/NHIEN&
0045: 31
0082 : W
0011 : 4202142782
0012: 041121
0009: G UNIT BRANDS INC.
0006: TH FLOOR HUDSON PLACE HOBOKEN NJ
1011: US
0330: 00134
0269: GREEN LIGHT GANG
1021: *GREEN/LIGHT/GANG&
1021: *GREEN/LIGHT&
0045: 25
0082 : W

Answer 1

Start by creating a List to hold the final result:

List<List<String>> finalList = new ArrayList<>();

Iterate through the current Main Data List of sub-lists but first create another List<String> listItems = new ArrayList<>(); to hold the item from Main List currently being processed. If the end of a sub-list is encountered that does not end with "W" then add it to the listItems list and then add the listItems list to the finalList. Essentially, we ignore sub-lists that end with "0082: W". Below is an example of this process (read all the comments in code):

// Holds the main List read in from file.
List<String> mainList = new ArrayList<>();
    
/* Will hold the List result after processing. 
   This result will overwrite the list above 
   when all is done.                      */
List<List<String>> finalList = new ArrayList<>();

// The data file that contains List Items.
String dataFilePath = "MainList.txt";
    
// Read in List data from file...
try (Scanner reader = new Scanner(new File(dataFilePath))) {
    while (reader.hasNextLine()) {
        mainList.add(reader.nextLine());
    }
}
catch (FileNotFoundException ex) {
    // Do what you like with Exception...
    System.err.println(ex.getMessage());
}

/* Iterate through the Main List. Ignore Sub-Lists 
   which contains "0082 : W"                   */
List<String> listItems = new ArrayList<>(); // Create a List for currently processed sub-list items
for (String lstStrg : mainList) {
    /* If line starts with "0082" to indicate the end of a sub-list
       but does NOT end with a "W" then...           */
    if (lstStrg.startsWith("0082") && !lstStrg.endsWith("W")) {
        listItems.add(lstStrg); // Add item to current list
        finalList.add(new ArrayList<>(listItems)); // Add the current list to final List as a new list object
        listItems.clear();  // Clear the current active list in prep for a new sub-list.
    }
    /* If line starts with "0082" to indicate the end of a sub-list
       but DOES end with a "W" then Clear the current active list in 
       prep for a new sub-list.  */
    else if (lstStrg.startsWith("0082") && lstStrg.endsWith("W")) {
        listItems.clear();
    }
    /* Otherwise just add Main List sub-list item to the 
       current active list.            */
    else {
        listItems.add(lstStrg);
    }
}
    
/* Clear the Main List then copy the Final Result List into
   the Original Main List. This will then be the same as
   though all Sub-Lists that ended with "0082 : W" were deleted. */
mainList.clear();
for (List<String> lst : finalList) {
    mainList.addAll(lst);
}
            
// Display the Main List with the results of this operation.
for (String strg : mainList) {
    System.out.println(strg);
}