Ordering cols

src/main/java/io/github/millij/poi/ss/model/annotations/SheetColumn.java

@@ -25,6 +25,16 @@
      * @return column name/header.
      */
     String value() default "";
+
+    int index() default 999999999;
+
+
+//    boolean isFormatted() default false;
+//    String format() default "dd/MM/yyyy";
+//    
+//    boolean isFromula() default false;
+
+
 
     /**
      * Setting this to <code>false</code> will enable the null check on the Column values, to ensure

src/main/java/io/github/millij/poi/ss/writer/SpreadsheetWriter.java

@@ -66,7 +66,7 @@ public <EB> void addSheet(Class<EB> beanType, List<EB> rowObjects) {
     }
 
     public <EB> void addSheet(Class<EB> beanType, List<EB> rowObjects, List<String> headers) {
-        // SheetName
+        // SheetNameindex
         Sheet sheet = beanType.getAnnotation(Sheet.class);
         String sheetName = sheet != null ? sheet.value() : null;
 

src/main/java/io/github/millij/poi/util/Spreadsheet.java

@@ -10,6 +10,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import org.apache.commons.beanutils.BeanUtils;
 import org.apache.commons.lang3.StringUtils;
@@ -102,9 +103,41 @@ public static Map<String, String> getColumnToPropertyMap(Class<?> beanType) {
     public static List<String> getColumnNames(Class<?> beanType) {
         // Bean Property to Column Mapping
         final Map<String, String> propToColumnMap = getPropertyToColumnNameMap(beanType);
-
-        final ArrayList<String> columnNames = new ArrayList<>(propToColumnMap.values());
-        return columnNames;
+        final Map<Integer,String> indexToPropMap = getColumnIndexToPropertyMap(beanType);
+
+        if(indexToPropMap.size() > 1) {
+
+        	Set<Integer> indexes = indexToPropMap.keySet();
+            List<Integer> indexList = new ArrayList<Integer>(indexes);
+            Collections.sort(indexList);
+
+            ArrayList<String> columnNames = new ArrayList<>();
+
+            for(Integer index : indexToPropMap.keySet())
+            {
+            	String colValue = propToColumnMap.get(indexToPropMap.get(index));
+            	columnNames.add(colValue);
+            }
+
+            ArrayList<String> columnNamesDup = new ArrayList<>(propToColumnMap.values());
+
+            for(String str : columnNamesDup)
+            {
+            	if(columnNames.contains(str)){
+            		continue;
+            	}
+            	else{
+            		columnNames.add(str);
+            	}
+            }
+            return columnNames;
+        }
+        else {
+        	ArrayList<String> columnNames = new ArrayList<>(propToColumnMap.values());
+        	return columnNames;
+        }
+
+
     }
 
 
@@ -199,6 +232,45 @@ public static <T> T rowAsBean(Class<T> beanClz, Map<String, String> cellProperie
         return null;
     }
 
+
+    public static Map<Integer,String> getColumnIndexToPropertyMap(Class<?> beanType) {
+        // Sanity checks
+        if (beanType == null) {
+            throw new IllegalArgumentException("getColumnToIndexMap :: Invalid ExcelBean type - " + beanType);
+        }
+
+        // Property to Column Index Mapping
+        final Map<Integer,String> mapping = new HashMap<Integer,String>();
+
+        // Fields
+        Field[] fields = beanType.getDeclaredFields();
+        for (Field f : fields) {
+            String fieldName = f.getName();
+
+            SheetColumn ec = f.getAnnotation(SheetColumn.class);
+
+            if (ec != null) {
+                int index = ec.index();
+                mapping.put(index,fieldName);
+            }
+        }
+
+        // Methods
+        Method[] methods = beanType.getDeclaredMethods();
+        for (Method m : methods) {
+            String fieldName = Beans.getFieldName(m);
+
+            SheetColumn ec = m.getAnnotation(SheetColumn.class);
+
+            if (ec != null) {
+                int index = ec.index();
+                mapping.put(index,fieldName);
+            }
+        }
+
+        LOGGER.info("Bean property to Excel Column of - {} : {}", beanType, mapping);
+        return Collections.unmodifiableMap(mapping);
+    }
 
 
 }

src/test/java/indexingCols/IndexedHeaderWriteTest.java

@@ -0,0 +1,44 @@
+package indexingCols;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Test;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import io.github.millij.bean.Emp_indexed;
+import io.github.millij.bean.Employee;
+import io.github.millij.poi.ss.model.annotations.SheetColumn;
+import io.github.millij.poi.ss.writer.SpreadsheetWriter;
+import io.github.millij.poi.ss.writer.SpreadsheetWriterTest;
+
+public class IndexedHeaderWriteTest
+{
+	private static final Logger LOGGER = LoggerFactory.getLogger(SpreadsheetWriterTest.class);
+
+    private final String _path_test_output = "test-cases/output/";
+
+
+
+    @Test
+    public void test_write_xlsx_single_sheet() throws IOException {
+        final String filepath_output_file = _path_test_output.concat("indexed_header_sample.xlsx");
+
+        // Excel Writer
+        LOGGER.info("test_write_xlsx_single_sheet :: Writing to file - {}", filepath_output_file);
+        SpreadsheetWriter gew = new SpreadsheetWriter(filepath_output_file);
+
+        // Employees
+        List<Emp_indexed> employees = new ArrayList<Emp_indexed>();
+        employees.add(new Emp_indexed("1", "foo", 12, "MALE", 1.68,"Chennai"));
+        employees.add(new Emp_indexed("2", "bar", 24, "MALE", 1.98,"Banglore"));
+        employees.add(new Emp_indexed("3", "foo bar", 10, "FEMALE",2.0,"Kolkata"));
+
+        // Write
+        gew.addSheet(Emp_indexed.class, employees);
+        gew.write();
+    }
+
+}

src/test/java/io/github/millij/bean/Emp_indexed.java

@@ -0,0 +1,100 @@
+package io.github.millij.bean;
+
+import io.github.millij.poi.ss.model.annotations.SheetColumn;
+
+public class Emp_indexed 
+{
+	private String id;
+	private String name;
+
+	@SheetColumn(value="Age",index=4)
+	private Integer age;
+
+	@SheetColumn(value="Gender")
+	private String gender;
+
+	@SheetColumn(value="Height (mts)",index=2)
+	private Double height;
+
+	@SheetColumn(value="Address")
+	private String address;
+
+
+	public Emp_indexed() {
+		// Default
+	}
+
+	public Emp_indexed(String id, String name, Integer age, String gender, Double height,String address) {
+		super();
+
+		this.id = id;
+		this.name = name;
+		this.age = age;
+		this.gender = gender;
+		this.height = height;
+		this.address = address;
+
+	}
+
+
+
+	@SheetColumn(value="ID")
+	public String getId() {
+		return id;
+	}
+
+	public void setId(String id) {
+		this.id = id;
+	}
+
+	@SheetColumn(value="Name",index=5)
+	public String getName() {
+		return name;
+	}
+
+	public void setName(String name) {
+		this.name = name;
+	}
+
+	public Integer getAge() {
+		return age;
+	}
+
+	public void setAge(Integer age) {
+		this.age = age;
+	}
+
+	public String getGender() {
+		return gender;
+	}
+
+	public void setGender(String gender) {
+		this.gender = gender;
+	}
+
+	public Double getHeight() {
+		return height;
+	}
+
+	public void setHeight(Double height) {
+		this.height = height;
+	}
+
+	public String getAddress() {
+		return address;
+	}
+
+	public void setAddress(String address) {
+		this.address = address;
+	}
+
+	@Override
+	public String toString() {
+		return "Emp_indexed [id=" + id + ", name=" + name + ", age=" + age + ", gender=" + gender + ", height=" + height
+				+ ", address=" + address + "]";
+	}
+
+
+
+}
+