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Add Java implementation of COBOL merge sort program #31

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e10aa36
Add Java implementation of COBOL merge sort program
devin-ai-integration[bot] Aug 19, 2025
b3d130f
Fix Java output format to match COBOL exactly
devin-ai-integration[bot] Aug 19, 2025
ccdc4c8
Fix CustomerRecord parsing to handle trimmed records
devin-ai-integration[bot] Aug 19, 2025
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Binary file added merge_sort/java/CustomerRecord.class
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117 changes: 117 additions & 0 deletions merge_sort/java/CustomerRecord.java
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public class CustomerRecord {
private String customerID;
private String lastName;
private String firstName;
private String contractID;
private String comment;

public CustomerRecord() {
}

public CustomerRecord(String customerID, String lastName, String firstName, String contractID, String comment) {
this.customerID = padOrTruncate(customerID, 5, true);
this.lastName = padOrTruncate(lastName, 50, false);
this.firstName = padOrTruncate(firstName, 50, false);
this.contractID = padOrTruncate(contractID, 5, true);
this.comment = padOrTruncate(comment, 25, false);
}

private String padOrTruncate(String value, int length, boolean isNumeric) {
if (value == null) {
value = "";
}

if (isNumeric) {
while (value.length() < length) {
value = "0" + value;
}
} else {
while (value.length() < length) {
value = value + " ";
}
}

if (value.length() > length) {
value = value.substring(0, length);
}

return value;
}

public String getCustomerID() {
return customerID;
}

public void setCustomerID(String customerID) {
this.customerID = padOrTruncate(customerID, 5, true);
}

public String getLastName() {
return lastName;
}

public void setLastName(String lastName) {
this.lastName = padOrTruncate(lastName, 50, false);
}

public String getFirstName() {
return firstName;
}

public void setFirstName(String firstName) {
this.firstName = padOrTruncate(firstName, 50, false);
}

public String getContractID() {
return contractID;
}

public void setContractID(String contractID) {
this.contractID = padOrTruncate(contractID, 5, true);
}

public String getComment() {
return comment;
}

public void setComment(String comment) {
this.comment = padOrTruncate(comment, 25, false);
}

public String toFixedWidthString() {
String result = customerID + lastName + firstName + contractID + comment;
return result.replaceAll("\\s+$", "");
}

public static CustomerRecord fromFixedWidthString(String line) {
if (line == null || line.length() < 115) {
return null;
}

while (line.length() < 135) {
line = line + " ";
}

CustomerRecord record = new CustomerRecord();
record.customerID = line.substring(0, 5);
record.lastName = line.substring(5, 55);
record.firstName = line.substring(55, 105);
record.contractID = line.substring(105, 110);
record.comment = line.substring(110, 135);

return record;
}

@Override
public String toString() {
return toFixedWidthString();
}

public int getCustomerIDAsInt() {
return Integer.parseInt(customerID.trim());
}

public int getContractIDAsInt() {
return Integer.parseInt(contractID.trim());
}
}
Binary file added merge_sort/java/FileReader.class
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28 changes: 28 additions & 0 deletions merge_sort/java/FileReader.java
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import java.io.BufferedReader;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;

public class FileReader {

public static List<CustomerRecord> readCustomerRecords(String filename) {
List<CustomerRecord> records = new ArrayList<>();

try (BufferedReader reader = Files.newBufferedReader(Paths.get(filename))) {
String line;
while ((line = reader.readLine()) != null) {
CustomerRecord record = CustomerRecord.fromFixedWidthString(line);
if (record != null) {
records.add(record);
}
}
} catch (IOException e) {
System.err.println("Error reading file " + filename + ": " + e.getMessage());
return new ArrayList<>();
}

return records;
}
}
Binary file added merge_sort/java/FileWriter.class
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19 changes: 19 additions & 0 deletions merge_sort/java/FileWriter.java
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import java.io.BufferedWriter;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.List;

public class FileWriter {

public static void writeCustomerRecords(List<CustomerRecord> records, String filename) {
try (BufferedWriter writer = Files.newBufferedWriter(Paths.get(filename))) {
for (CustomerRecord record : records) {
writer.write(record.toFixedWidthString());
writer.newLine();
}
} catch (IOException e) {
System.err.println("Error writing file " + filename + ": " + e.getMessage());
}
}
}
Binary file added merge_sort/java/MergeSortProcessor.class
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84 changes: 84 additions & 0 deletions merge_sort/java/MergeSortProcessor.java
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import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;

public class MergeSortProcessor {

public static void main(String[] args) {
createTestData();
mergeAndDisplayFiles();
sortAndDisplayFile();
System.out.println("Done.");
}

private static void createTestData() {
System.out.println("Creating test data files...");

List<CustomerRecord> testFile1Records = new ArrayList<>();
testFile1Records.add(new CustomerRecord("1", "last-1", "first-1", "5423", "comment-1"));
testFile1Records.add(new CustomerRecord("5", "last-5", "first-5", "12323", "comment-5"));
testFile1Records.add(new CustomerRecord("10", "last-10", "first-10", "653", "comment-10"));
testFile1Records.add(new CustomerRecord("50", "last-50", "first-50", "5050", "comment-50"));
testFile1Records.add(new CustomerRecord("25", "last-25", "first-25", "7725", "comment-25"));
testFile1Records.add(new CustomerRecord("75", "last-75", "first-75", "1175", "comment-75"));

List<CustomerRecord> testFile2Records = new ArrayList<>();
testFile2Records.add(new CustomerRecord("999", "last-999", "first-999", "1610", "comment-99"));
testFile2Records.add(new CustomerRecord("3", "last-03", "first-03", "3331", "comment-03"));
testFile2Records.add(new CustomerRecord("30", "last-30", "first-30", "8765", "comment-30"));
testFile2Records.add(new CustomerRecord("85", "last-85", "first-85", "4567", "comment-85"));
testFile2Records.add(new CustomerRecord("24", "last-24", "first-24", "247", "comment-24"));

FileWriter.writeCustomerRecords(testFile1Records, "test-file-1.txt");
FileWriter.writeCustomerRecords(testFile2Records, "test-file-2.txt");
}

private static void mergeAndDisplayFiles() {
System.out.println("Merging and sorting files...");

List<CustomerRecord> file1Records = FileReader.readCustomerRecords("test-file-1.txt");
List<CustomerRecord> file2Records = FileReader.readCustomerRecords("test-file-2.txt");

if (file1Records.isEmpty()) {
System.err.println("Error opening test-file-1.txt");
return;
}

if (file2Records.isEmpty()) {
System.err.println("Error opening test-file-2.txt");
return;
}

List<CustomerRecord> mergedRecords = new ArrayList<>();
mergedRecords.addAll(file1Records);
mergedRecords.addAll(file2Records);

Collections.sort(mergedRecords, Comparator.comparing(CustomerRecord::getCustomerIDAsInt));

FileWriter.writeCustomerRecords(mergedRecords, "merge-output.txt");

for (CustomerRecord record : mergedRecords) {
System.out.println(record.toFixedWidthString());
}
}

private static void sortAndDisplayFile() {
System.out.println("Sorting merged file on descending contract id....");

List<CustomerRecord> mergedRecords = FileReader.readCustomerRecords("merge-output.txt");

if (mergedRecords.isEmpty()) {
System.err.println("Error opening merge-output.txt");
return;
}

Collections.sort(mergedRecords, Comparator.comparing(CustomerRecord::getContractIDAsInt).reversed());

FileWriter.writeCustomerRecords(mergedRecords, "sorted-contract-id.txt");

for (CustomerRecord record : mergedRecords) {
System.out.println(record.toFixedWidthString());
}
}
}
11 changes: 11 additions & 0 deletions merge_sort/java/merge-output.txt
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00001last-1 first-1 05423comment-1
00003last-03 first-03 03331comment-03
00005last-5 first-5 12323comment-5
00010last-10 first-10 00653comment-10
00024last-24 first-24 00247comment-24
00025last-25 first-25 07725comment-25
00030last-30 first-30 08765comment-30
00050last-50 first-50 05050comment-50
00075last-75 first-75 01175comment-75
00085last-85 first-85 04567comment-85
00999last-999 first-999 01610comment-99
11 changes: 11 additions & 0 deletions merge_sort/java/sorted-contract-id.txt
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00005last-5 first-5 12323comment-5
00030last-30 first-30 08765comment-30
00025last-25 first-25 07725comment-25
00001last-1 first-1 05423comment-1
00050last-50 first-50 05050comment-50
00085last-85 first-85 04567comment-85
00003last-03 first-03 03331comment-03
00999last-999 first-999 01610comment-99
00075last-75 first-75 01175comment-75
00010last-10 first-10 00653comment-10
00024last-24 first-24 00247comment-24
6 changes: 6 additions & 0 deletions merge_sort/java/test-file-1.txt
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00001last-1 first-1 05423comment-1
00005last-5 first-5 12323comment-5
00010last-10 first-10 00653comment-10
00050last-50 first-50 05050comment-50
00025last-25 first-25 07725comment-25
00075last-75 first-75 01175comment-75
5 changes: 5 additions & 0 deletions merge_sort/java/test-file-2.txt
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00999last-999 first-999 01610comment-99
00003last-03 first-03 03331comment-03
00030last-30 first-30 08765comment-30
00085last-85 first-85 04567comment-85
00024last-24 first-24 00247comment-24