implement validation logic

src/main/java/com/nisum/Employeeinfo/advice/EmployeeServiceException.java

+package com.nisum.Employeeinfo.advice;
+
+import com.nisum.Employeeinfo.errorcode.ApiError;
+import com.nisum.Employeeinfo.errorcode.ApiErrorCode;
+import com.nisum.Employeeinfo.exception.EmployeeNotFoundException;
+import com.nisum.Employeeinfo.exception.ExceptionResponse;
+import com.nisum.Employeeinfo.exception.InvalidEmployeeDataException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.server.reactive.ServerHttpRequest;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RestControllerAdvice;
+
+@RestControllerAdvice
+public class EmployeeServiceException {
+
+    @ExceptionHandler(EmployeeNotFoundException.class)
+    public ResponseEntity<Object> handleEmployeeNotFoundException(EmployeeNotFoundException ex, ServerHttpRequest serverHttpRequest){
+
+        ApiError apiError= new ApiError(
+                ex.getErrorCode(),
+                ex.getMessage(),
+                serverHttpRequest.getURI().getPath()
+        );
+        ExceptionResponse response=new ExceptionResponse(apiError);
+        return new ResponseEntity<>(response, HttpStatus.NOT_FOUND);
+    }
+
+    @ExceptionHandler(InvalidEmployeeDataException.class)
+    public ResponseEntity<Object> handleInvalidEmployeeData(InvalidEmployeeDataException ex, ServerHttpRequest serverHttpRequest){
+
+        ApiError apiError= new ApiError(
+                ex.getErrorCode(),
+                ex.getMessage(),
+                serverHttpRequest.getURI().getPath()
+        );
+        ExceptionResponse response=new ExceptionResponse(apiError);
+        return new ResponseEntity<>(response, HttpStatus.BAD_REQUEST);
+    }
+
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<Object> handleGeneralException(Exception ex, ServerHttpRequest serverHttpRequest){
+
+        ApiError apiError= new ApiError(
+                ApiErrorCode.GENERAL_ERROR.getString(),
+                ex.getMessage(),
+                serverHttpRequest.getURI().getPath()
+        );
+        ExceptionResponse response=new ExceptionResponse(apiError);
+        return new ResponseEntity<>(response, HttpStatus.INTERNAL_SERVER_ERROR);
+    }
+
+}

src/main/java/com/nisum/Employeeinfo/errorcode/ApiError.java

+package com.nisum.Employeeinfo.errorcode;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class ApiError {
+
+    @JsonProperty("errorCode")
+    private String errorCode;
+    @JsonProperty("errorMessage")
+    private String errorMessage;
+    @JsonProperty("uri")
+    private String uri;
+
+
+
+    public ApiError(String errorCode, String errorMessage,  String uri) {
+        this.errorCode = errorCode;
+        this.errorMessage = errorMessage;
+        this.uri = uri;
+    }
+
+    public String getErrorCode() {
+        return errorCode;
+    }
+
+    public void setErrorCode(String errorCode) {
+        this.errorCode = errorCode;
+    }
+
+    public String getErrorMessage() {
+        return errorMessage;
+    }
+
+    public void setErrorMessage(String errorMessage) {
+        this.errorMessage = errorMessage;
+    }
+
+    public String getUri() {
+        return uri;
+    }
+
+    public void setUri(String uri) {
+        this.uri = uri;
+    }
+}

src/main/java/com/nisum/Employeeinfo/errorcode/ApiErrorCode.java

+package com.nisum.Employeeinfo.errorcode;
+
+import com.fasterxml.jackson.annotation.JsonValue;
+
+public enum ApiErrorCode {
+
+    EMPLOYEE_NOT_FOUND("EMPLOYEE_404"),
+    INVALID_EMPLOYEE_DATA("EMPLOYEE_400"),
+    EMPLOYEE_CREATION_FAILED("EMPLOYEE_500"),
+    EMPLOYEE_UPDATE_FAILED("EMPLOYEE_500"),
+    EMPLOYEE_DELETION_FAILED("EMPLOYEE_500"),
+    GENERAL_ERROR("GENERAL_500");
+
+
+
+    private final String errorCode;
+
+    // Constructor
+    private ApiErrorCode(String errorCode) {
+        this.errorCode = errorCode;
+    }
+
+    // Method to return the error code as a string
+    @JsonValue
+    public String getString() {
+        return this.errorCode;
+    }
+
+}

src/main/java/com/nisum/Employeeinfo/exception/EmployeeNotFoundException.java

+package com.nisum.Employeeinfo.exception;
+
+import com.nisum.Employeeinfo.errorcode.ApiErrorCode;
+
+public class EmployeeNotFoundException extends RuntimeException  {
+
+    private static final long serialVersionUID = -4918194282229127629L;
+
+    private final String errorCode;
+
+    // Constructor that accepts ApiErrorCode and message
+    public EmployeeNotFoundException(ApiErrorCode apiErrorCode, String message) {
+        super(message); // Pass message to RuntimeException constructor
+        this.errorCode = apiErrorCode.getString(); // Store the error code from ApiErrorCode
+    }
+
+    // Getter for errorCode
+    public String getErrorCode() {
+        return errorCode;
+    }
+}
+

src/main/java/com/nisum/Employeeinfo/exception/ExceptionResponse.java

+package com.nisum.Employeeinfo.exception;
+
+import com.nisum.Employeeinfo.errorcode.ApiError;
+
+public class ExceptionResponse {
+
+
+
+    private ApiError apiError;
+
+    public ExceptionResponse(ApiError error) {
+        apiError=new ApiError(
+                error.getErrorCode(),
+                error.getErrorMessage(),
+                error.getUri()
+                );
+    }
+
+    public ApiError getApiError() {
+        return apiError;
+    }
+
+    public void setApiError(ApiError apiError) {
+        this.apiError = apiError;
+    }
+}

src/main/java/com/nisum/Employeeinfo/exception/InvalidEmployeeDataException.java

+package com.nisum.Employeeinfo.exception;
+
+import com.nisum.Employeeinfo.errorcode.ApiErrorCode;
+
+public class InvalidEmployeeDataException extends RuntimeException{
+
+
+    private final String errorCode;
+
+    public InvalidEmployeeDataException(ApiErrorCode errorCode, String message){
+
+        super(message);
+        this.errorCode=errorCode.getString();
+
+    }
+    public String getErrorCode() {
+        return errorCode;
+    }
+}

src/main/java/com/nisum/Employeeinfo/validator/CommonServiceValidator.java

+package com.nisum.Employeeinfo.validator;
+
+public class CommonServiceValidator {
+}