CodelineAtyab · TibyanSaad · May 24, 2026 · May 24, 2026 · May 24, 2026 · May 24, 2026
diff --git a/ChangeLog.md b/ChangeLog.md
@@ -0,0 +1,39 @@
+# Change Log
+
+## Version[0.0.6] - 24-05-2026
+### Fixed
+- `Sequence.java`: removed all JPA annotations, now a pure domain object. `value` field changed from comma-separated `String` to `List<String>` directly. Added `setId()` and `setTimestamp()` setters.
+- `SequenceHistory.java`: new class that takes over all JPA annotations and DB mapping from `Sequence`. Handles comma-separated conversion of `value` via `fromSequence()` and `toSequence()` methods.
+- `SequenceRepo.java`: updated to use `SequenceHistory` instead of `Sequence` as the JPA entity.
+- `SequenceService.java`: added `saveAndReturn()` helper to handle `Sequence` ↔ `SequenceHistory` conversion on every save. Added `getAllHistory()` for raw DB access. Added `MAX_Z_CHAIN = 100` constant and full edge case handling in `computeValues()`.
+- `SequenceController.java`: added `GET /convert-measurements/history` endpoint that returns raw `SequenceHistory` records from the DB.
+
+## Version[0.0.5] - 22-05-2026
+### Fixed
+- User is able to check all the history records of previous requests.
+- Added GET request query for specific IDs.
+
+## Version[0.0.4] - 22-05-2026
+### Fixed
+- Added `SequenceRepo` interface for DB connection.
+- Established a connection with the DB and tested with multiple requests.
+- PUT request now works with raw JSON format to update input value.
+
+## Version[0.0.3] - 21-05-2026
+### Fixed
+- Added PUT request to edit using input with endpoint `/convert-measurements/{id}`
+- Added DELETE request with endpoint `/convert-measurements/{id}`.
+- fixed error related to getting source IP rather than ServerSocket used HttpServletRequest.
+
+## Version[0.0.2] - 21-05-2026
+### Fixed
+- User input is converted to lower case.
+- Handled invalid user input (numbers and special characters).
+
+## Version[0.0.1] - 21-05-2026
+### Added
+- Initial release of Sequence Measurement API.
+- Core algorithm for decoding measurement sequences ("SequenceService") with z-multiplier encoding.
+- Spring Boot server with `/convert-measurements` endpoint returning decoded sums.
+- Sequence model with auto-generated ID and timestamp.
+- Application startup check in `SequenceMeasurementApiApplicationTests.java`.
diff --git a/pom.xml b/pom.xml
@@ -1,34 +1,23 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+		 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
 	<modelVersion>4.0.0</modelVersion>
 	<parent>
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
 		<version>3.5.14</version>
-		<relativePath/> <!-- lookup parent from repository -->
+		<relativePath/>
 	</parent>
 	<groupId>com.oraclequantapi</groupId>
 	<artifactId>oraclequantapi</artifactId>
-	<version>0.0.1-SNAPSHOT</version>
-	<name/>
-	<description/>
-	<url/>
-	<licenses>
-		<license/>
-	</licenses>
-	<developers>
-		<developer/>
-	</developers>
-	<scm>
-		<connection/>
-		<developerConnection/>
-		<tag/>
-		<url/>
-	</scm>
+	<version>0.0.1</version>
+	<name>oraclequantapi</name>
+	<description>Sequence Measurement API</description>
+
 	<properties>
 		<java.version>17</java.version>
 	</properties>
+
 	<dependencies>
 		<dependency>
 			<groupId>org.springframework.boot</groupId>
@@ -40,15 +29,38 @@
 			<artifactId>spring-boot-starter-test</artifactId>
 			<scope>test</scope>
 		</dependency>
+
+		<!-- Oracle JDBC -->
+		<dependency>
+			<groupId>com.oracle.database.jdbc</groupId>
+			<artifactId>ojdbc11</artifactId>
+			<version>23.3.0.23.09</version>
+		</dependency>
+
+		<!-- Spring Data JPA -->
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
 	</dependencies>
 
 	<build>
 		<plugins>
 			<plugin>
 				<groupId>org.springframework.boot</groupId>
 				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<mainClass>com.oraclequantapi.oraclequantapi.OraclequantapiApplication</mainClass>
+				</configuration>
+				<executions>
+					<execution>
+						<goals>
+							<goal>repackage</goal>
+						</goals>
+					</execution>
+				</executions>
 			</plugin>
 		</plugins>
 	</build>
 
-</project>
+</project>
diff --git a/src/main/java/com/oraclequantapi/oraclequantapi/README.md b/src/main/java/com/oraclequantapi/oraclequantapi/README.md
@@ -0,0 +1,254 @@
+# Sequence Measurement API
+
+A Spring Boot REST API that decodes a string encoding format and stores the results in an Oracle XE database.
+
+---
+
+## Encoding Format
+
+Each input string is made up of back-to-back packages. The encoding rules are:
+
+- Characters map to values: `_` = 0, `a` = 1, `b` = 2, ... `y` = 25, `z` = 26
+- `z` is the only non-terminating character — it means "add 26 and keep reading"
+- Any character that is not `z` terminates the current number
+- Each package starts with a count, followed by exactly that many encoded values
+- The result of each package is the sum of its decoded values
+- The final output is a list of sums, one per package
+### Example
+
+| Input | Decoded | Output |
+|-------|---------|--------|
+| `abbcc` | Package 1: count=1, values=[2] → Package 2: count=2, values=[3,3] | `[2, 6]` |
+| `czzabzc` | Package 1: count=3, values=[53, 2, 29] | `[53, 2, 29]` |
+| `dz_a_aazzaaa` | Package 1: count=4, values=[26,1,0,1] → Package 2: count=1, values=[53] → Package 3: count=1, values=[1] | `[28, 53, 1]` |
+
+---
+
+## Architecture
+
+The project is split into four layers:
+
+- **`Sequence`** — pure domain object, no JPA annotations, holds business logic and validation
+- **`SequenceHistory`** — JPA entity, owns all database mapping, converts to/from `Sequence` via `fromSequence()` and `toSequence()`
+- **`SequenceService`** — business logic layer, bridges domain and persistence
+- **`SequenceController`** — REST layer, exposes all endpoints
+- **`SequenceRepo`** — JPA repository interface for Oracle XE
+---
+
+## Endpoints
+
+| Method | URL | Description |
+|--------|-----|-------------|
+| `GET` | `/convert-measurements?input=abbcc` | Decode a new input string and store the result |
+| `GET` | `/convert-measurements/{id}` | Fetch a specific record by ID |
+| `GET` | `/convert-measurements/all` | Fetch all records as domain objects |
+| `GET` | `/convert-measurements/history` | Fetch all raw records directly from the DB |
+| `PUT` | `/convert-measurements/{id}` | Update the input of an existing record and re-decode |
+| `DELETE` | `/convert-measurements/{id}` | Delete a specific record by ID |
+
+### PUT Request Body
+```json
+{
+    "input": "abbcc"
+}
+```
+
+---
+
+## Validation
+
+- Only lowercase letters `a-z` and underscore `_` are allowed in the input
+- Capital letters are automatically converted to lowercase
+- Any other character (numbers, special characters) returns `"invalid sequence format"`
+---
+
+## Edge Cases
+
+The decoder handles the following malformed inputs:
+
+| Edge Case | Response |
+|-----------|----------|
+| Zero count package | `"0"` |
+| Fewer values than count | `"malformed package: expected X values but found Y"` |
+| Unterminated z-chain | `"malformed package: unterminated number"` |
+| Z-chain exceeds 100 characters | `"malformed package: number exceeds maximum allowed size"` |
+| Single character count with no values | `"malformed package: expected X values but found 0"` |
+
+---
+
+## Setup
+
+### Prerequisites
+- Java 17
+- Spring Boot
+- Oracle XE database
+- Maven
+### `application.properties`
+```properties
+spring.datasource.url=jdbc:oracle:thin:@localhost:1521:XE
+spring.datasource.username=your_username
+spring.datasource.password=your_password
+spring.datasource.driver-class-name=oracle.jdbc.OracleDriver
+
+spring.jpa.hibernate.ddl-auto=update
+spring.jpa.show-sql=true
+spring.jpa.open-in-view=false
+spring.datasource.hikari.auto-commit=true
+```
+
+### Database Setup
+Run the following in your Oracle XE SQL client:
+```sql
+CREATE TABLE SEQUENCES (
+    ID          NUMBER(19)      NOT NULL,
+    INPUT       VARCHAR2(4000),
+    SOURCE_IP   VARCHAR2(100),
+    TIMESTAMP   TIMESTAMP,
+    OUTPUT      VARCHAR2(2000),
+    CONSTRAINT PK_SEQUENCES PRIMARY KEY (ID)
+);
+
+CREATE SEQUENCE SEQUENCE_SEQ
+    START WITH 1
+    INCREMENT BY 1
+    NOCACHE
+    NOCYCLE;
+```
+
+### Running the API Locally
+```bash
+mvn spring-boot:run
+```
+
+The API will be available at `http://localhost:8080`
+
+---
+
+## Deploying as a Service on Oracle Linux
+
+The API is packaged as `oraclequantapi-0.0.1.jar` and runs as a `systemd` service on Oracle Linux.
+
+### Prerequisites
+- Java 17 installed on the server
+- The JAR file transferred to the server
+### Step 1 — Verify Java is installed
+```bash
+java -version
+```
+If not installed, run:
+```bash
+sudo dnf install java-17-openjdk -y
+```
+
+### Step 2 — Create the application directory
+```bash
+sudo mkdir -p /opt/oraclequantapi
+sudo cp oraclequantapi-0.0.1.jar /opt/oraclequantapi/oraclequantapi-0.0.1.jar
+```
+
+### Step 3 — Create the systemd service file
+```bash
+sudo nano /etc/systemd/system/oraclequantapi.service
+```
+
+Paste the following:
+```ini
+[Unit]
+Description=Oracle Quant API Spring Boot Service
+After=network.target
+
+[Service]
+User=root
+WorkingDirectory=/opt/oraclequantapi
+ExecStart=/usr/bin/java -jar /opt/oraclequantapi/oraclequantapi-0.0.1.jar
+SuccessExitStatus=143
+StandardOutput=journal
+StandardError=journal
+SyslogIdentifier=oraclequantapi
+Restart=on-failure
+RestartSec=10
+
+[Install]
+WantedBy=multi-user.target
+```
+
+### Step 4 — Reload systemd and enable the service
+```bash
+# Reload systemd to pick up the new service file
+sudo systemctl daemon-reload
+
+# Enable the service to start automatically on boot
+sudo systemctl enable oraclequantapi
+
+# Start the service
+sudo systemctl start oraclequantapi
+```
+
+### Step 5 — Verify the service is running
+```bash
+sudo systemctl status oraclequantapi
+```
+
+You should see:
+```
+● oraclequantapi.service - Oracle Quant API Spring Boot Service
+     Loaded: loaded (/etc/systemd/system/oraclequantapi.service; enabled)
+     Active: active (running)
+```
+
+### Managing the Service
+
+| Command | Description |
+|---------|-------------|
+| `sudo systemctl start oraclequantapi` | Start the service |
+| `sudo systemctl stop oraclequantapi` | Stop the service |
+| `sudo systemctl restart oraclequantapi` | Restart the service |
+| `sudo systemctl status oraclequantapi` | Check service status |
+| `sudo systemctl enable oraclequantapi` | Enable on boot |
+| `sudo systemctl disable oraclequantapi` | Disable on boot |
+
+### Viewing Logs
+```bash
+# View live logs
+sudo journalctl -u oraclequantapi -f
+
+# View last 100 lines
+sudo journalctl -u oraclequantapi -n 100
+```
+
+---
+
+## Example Requests
+
+### Decode a new sequence
+```
+GET http://localhost:8080/convert-measurements?input=abbcc
+```
+Response:
+```json
+["2", "6"]
+```
+
+### Update an existing sequence
+```
+PUT http://localhost:8080/convert-measurements/1
+```
+Body:
+```json
+{
+    "input": "czzabzc"
+}
+```
+Response:
+```json
+["84"]
+```
+
+### Delete a sequence
+```
+DELETE http://localhost:8080/convert-measurements/1
+```
+Response:
+```
+Sequence 1 deleted successfully
+```