Basic Auto Gen Class Util

AutoGenClassUtil.java

package com.autogenclass;

import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;
import java.util.stream.Stream;

public class AutoGenClassUtil {

	public static void main(String[] args) {
		String filePath = "/home/hduser/codebase/CoreJava8Assignments/src/main/java/com/autogenclass/Customer.txt";
		String fileName = Paths.get(filePath).getFileName().toString();
		fileName = (fileName != null && fileName.lastIndexOf(".") > 0)
				? fileName.substring(0, fileName.lastIndexOf("."))
				: fileName;
		String generateAClassString = GetClassStructure.generateAClassString(fileName, filePath);
		try {
			new File("/home/hduser/codebase/CoreJava8Assignments/src/main/java/com/autogenclass/" + fileName + ".java")
					.delete();
			Files.write(Paths.get(
					"/home/hduser/codebase/CoreJava8Assignments/src/main/java/com/autogenclass/" + fileName + ".java"),
					generateAClassString.getBytes());
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
}

class ReadDataFromFile {

	public static String getClassName(String fileName) {
		String s1 = fileName.substring(0, 1).toUpperCase();
		String nameCapitalized = s1 + fileName.substring(1);
		return nameCapitalized;
	}

	public static String getFieldDataFromFile(String filePath) {
		List<String[]> list = null;
		try (Stream<String> stream = Files.lines(Paths.get(filePath))) {
			List<String> collect = stream.collect(Collectors.toList());
			list = new ArrayList<>();
			for (String line : collect) {
				String[] split = line.split(" ");
				if (split.length >= 2)
					list.add(split);
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		return String.join("", getFieldList(list));
	}

	public static List<String> getFieldList(List<String[]> fields) {
		List<String> list = new ArrayList<>();
		for (String[] strArry : fields) {
			list.add(genenrateFieldData(strArry[0], strArry[1]));
		}
		return list;
	}

	public static String genenrateFieldData(String fieldName, String fieldType) {
		String fieldTypeStr = "";
		if ("INT".equals(fieldType)) {
			System.out.println(FieldType.INT.getFieldType());
			fieldTypeStr = "\n\tprivate " + FieldType.INT.getFieldType() + " " + fieldName + ";";
		} else if ("VARCHAR".equals(fieldType)) {
			System.out.println(FieldType.INT.getFieldType());
			fieldTypeStr = "\n\tprivate " + FieldType.VARCHAR.getFieldType() + " " + fieldName + ";";
		} else if ("DATE".equals(fieldType)) {
			System.out.println(FieldType.DATE.getFieldType());
			fieldTypeStr = "\n\tprivate " + FieldType.DATE.getFieldType() + " " + fieldName + ";";
		}
		return fieldTypeStr;

	}
}

class GetClassStructure {

	public static String getClassDeclarationPart(String className) {
		return "package com.autogenclass; \n\npublic class " + className + " {";
	}

	public static String getClassEndPart() {
		return "\n}";
	}

	public static String generateAClassString(String fileName, String filePath) {
		return getClassDeclarationPart(fileName) + ReadDataFromFile.getFieldDataFromFile(filePath) + getClassEndPart();
	}
}

enum FieldType {
	INT("int"), VARCHAR("String"), DATE("java.time.LocalDate");

	private FieldType(final String fieldType) {
		this.fieldType = fieldType;
	}

	private String fieldType;

	public String getFieldType() {
		return fieldType;
	}
}

Customer.txt

id INT
name VARCHAR
date DATE