feat: Add Account POJO and AccountHandler with JDBC connection and query methods

[devin-ai-integration]

Summary

Adds the Java equivalent of the existing COBOL sql_example.cbl program under a new sql/java/ directory. This is the data-access foundation for the COBOL-to-Java migration of the PostgreSQL account querying program.

Two new files:

• Account.java — POJO mirroring the COBOL ws-account-record structure (8 fields: id, firstName, lastName, phone, address, isEnabled, createDt, modDt). All-args constructor, getters, toString().
• AccountHandler.java — JDBC connection manager with query methods that mirror the three COBOL cursors (ACCOUNT-ALL-CUR, ACCOUNT-DISABLED-CUR, ACCOUNT-QUERY-CUR):
  • connect() / disconnect() — lifecycle management
  • getAllAccounts() — all rows ordered by ID
  • getDisabledAccounts() — filtered to IS_ENABLED = 'N'
  • searchAccounts(String) — LIKE search across first name, last name, phone, address
  • displayAccounts(List<Account>) — tabular output matching the COBOL display-account-results paragraph format

All queries use PreparedStatement. Error handling prints SQL state, error code, and message (matching the COBOL check-sql-state pattern). Connection failure calls System.exit(1) to mirror the COBOL stop run behavior.

Both files compile cleanly against JDK 11.

Review & Testing Checklist for Human

• Verify displayAccounts column widths match the COBOL output format (ID:5, First:8, Last:8, Phone:10, Address:22, Enabled:1). Compare the printf format strings against the COBOL display-account-results paragraph (lines 400-430 of sql_example.cbl).
• Confirm searchAccounts null-safety — passing null would produce the LIKE pattern %null% (string concatenation). Decide if a null guard is needed or if this is acceptable for the migration scope.
• Review hardcoded DB credentials — DB_URL, DB_USER, DB_PASSWORD are plaintext constants matching the COBOL connection string. Acceptable for this example/migration repo, but flag if the project intends to externalize config later.
• End-to-end test: If a PostgreSQL instance is available, run create_test_db.sql, compile both files with the PostgreSQL JDBC driver on the classpath, and write a short main() to call connect() → getAllAccounts() → displayAccounts() → disconnect() to verify output matches the COBOL program.

Notes

• No Main.java is included — that will be a separate ticket.
• createDt / modDt are stored as String (matching the COBOL PIC X(20)) rather than java.sql.Timestamp. This is intentional for COBOL parity but could be revisited.
• Files are in the default package (no package declaration), consistent with the simple example nature of this repo.

Link to Devin session: https://app.devin.ai/sessions/0ebdc63cd333461ca6a0cce03146215a
Requested by: @Colhodm

---

[devin-ai-integration]

🤖 Devin AI Engineer

I'll be helping with this pull request! Here's what you should know:

✅ I will automatically:

• Address comments on this PR. Add '(aside)' to your comment to have me ignore it.
• Look at CI failures and help fix them

Note: I can only respond to comments from users who have write access to this repository.

⚙️ Control Options:

• Disable automatic comment and CI monitoring

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no potential bugs to report.

View in Devin Review to see 3 additional findings.