Added Support for JPA Entities export.

.gitignore

@@ -2,3 +2,5 @@
 /target
 /.classpath
 /.project
+.~users.xlsx
+users.xlsx

README.md

@@ -238,3 +238,22 @@ Add xcelite as a dependency:
 			<version>1.0.4</version>
 </dependency>
 ```
+### OR
+Add this repository as dependency, if you want support for Jpa data export. 
+```xml
+<repositories>
+	<repository>
+		<id>Github</id>
+		<name>Github repository</name>
+		<url>https://raw.github.com/boriswaguia/xcelite/release</url>
+	</repository>
+</repositories>
+```
+
+```xml
+<dependency>
+	<groupId>com.ebay</groupId>
+	<artifactId>xcelite</artifactId>
+	<version>1.0.5-SNAPSHOT</version>
+</dependency>
+```

pom.xml

@@ -2,7 +2,7 @@
 	<modelVersion>4.0.0</modelVersion>
 	<groupId>com.ebay</groupId>
 	<artifactId>xcelite</artifactId>
-	<version>1.0.5-SNAPSHOT</version>
+	<version>1.0.8-SNAPSHOT</version>
 	<packaging>jar</packaging>
 	<name>xcelite</name>
 	<description>Xcelite is an ORM like Java library which allows you to easily serialize and deserialize Java beans to/from Excel spreadsheets</description>
@@ -74,6 +74,9 @@
 				<groupId>org.apache.maven.plugins</groupId>
 				<artifactId>maven-javadoc-plugin</artifactId>
 				<version>2.9.1</version>
+				<configuration>
+					<additionalparam>-Xdoclint:none</additionalparam>
+				</configuration>
 				<executions>
 					<execution>
 						<id>attach-javadocs</id>
@@ -120,5 +123,18 @@
 			<artifactId>commons-collections</artifactId>
 			<version>3.2.1</version>
 		</dependency>
+		<!-- https://mvnrepository.com/artifact/org.hibernate.javax.persistence/hibernate-jpa-2.0-api -->
+		<dependency>
+		    <groupId>org.hibernate.javax.persistence</groupId>
+		    <artifactId>hibernate-jpa-2.0-api</artifactId>
+		    <version>1.0.1.Final</version>
+		</dependency>
+		<!-- https://mvnrepository.com/artifact/junit/junit -->
+		<dependency>
+		    <groupId>junit</groupId>
+		    <artifactId>junit</artifactId>
+		    <version>4.12</version>
+		    <scope>test</scope>
+		</dependency>
 	</dependencies>
 </project>

src/main/java/com/ebay/xcelite/column/Col.java

@@ -38,10 +38,16 @@ public Col(String name) {
   }
 
   public Col(String name, String fieldName) {
+	  this(name, fieldName, String.class);
+  }
+
+
+  public Col(String name, String fieldName, Class<?> type) {
     this.name = name;
     this.fieldName = fieldName;
-    type = String.class;
+    this.type = type;
   }
+
 
   @Override
   public String toString() {

src/main/java/com/ebay/xcelite/column/ColumnsExtractor.java

@@ -22,6 +22,9 @@
 import java.util.Map;
 import java.util.Set;
 
+import javax.persistence.JoinColumn;
+import javax.persistence.ManyToOne;
+
 import org.reflections.ReflectionUtils;
 
 import com.ebay.xcelite.annotate.NoConverterClass;
@@ -79,7 +82,7 @@ public void extract() {
         col.setConverter(annotation.converter());
       }
       columns.add(col);
-    }   
+    }
 
     if (colsOrdering != null) {
       orderColumns();
@@ -88,6 +91,48 @@ public void extract() {
     extractAnyColumn();
   }
 
+
+  @SuppressWarnings("unchecked")
+  public void extractJpa() {    
+    Set<Field> idFields = ReflectionUtils.getAllFields(type, withAnnotation(javax.persistence.Id.class));
+    Set<Field> columnFields = ReflectionUtils.getAllFields(type, withAnnotation(javax.persistence.Column.class));
+    Set<Field> manyToOneFields = ReflectionUtils.getAllFields(type, withAnnotation(javax.persistence.ManyToOne.class));
+
+    for (Field columnField : idFields) {
+      javax.persistence.Id annotation = columnField.getAnnotation(javax.persistence.Id.class);
+      if(annotation == null) continue;
+      Col col = null;
+      col = new Col(columnField.getName(), columnField.getName(), columnField.getType());
+      columns.add(col);
+    }
+
+    for (Field columnField : columnFields) {
+      javax.persistence.Column annotation = columnField.getAnnotation(javax.persistence.Column.class);
+      if(annotation == null) continue;
+      Col col = null;
+      if (annotation.name().isEmpty()) {
+        col = new Col(columnField.getName(), columnField.getName(),  columnField.getType());        
+      } else {
+        col = new Col(annotation.name(), columnField.getName(), columnField.getType());
+      }
+      columns.add(col);
+    }
+
+    for (Field columnField : manyToOneFields) {
+      ManyToOne annotation = columnField.getAnnotation(javax.persistence.ManyToOne.class);
+      Col col = null;
+      if(annotation == null) continue;
+      JoinColumn joinColumn = columnField.getAnnotation(javax.persistence.JoinColumn.class);
+      if (joinColumn.name().isEmpty()) {
+        col = new Col(columnField.getName(), columnField.getName(), columnField.getType());        
+      } else {
+        col = new Col(joinColumn.name(), columnField.getName(), columnField.getType());
+      }
+      columns.add(col);
+    }
+  }
+
+
   @SuppressWarnings("unchecked")
   private void extractAnyColumn() {
     Set<Field> anyColumnFields = ReflectionUtils.getAllFields(type, withAnnotation(AnyColumn.class));    
@@ -108,7 +153,7 @@ private void extractAnyColumn() {
       if (annotation.converter() != NoConverterClass.class) {
         anyColumn.setConverter(annotation.converter());
       }
-    }    
+    }
   }
 
   private void orderColumns() {

src/main/java/com/ebay/xcelite/reader/BeanSheetReader.java

@@ -26,6 +26,7 @@
 import java.util.Map;
 import java.util.Set;
 
+import org.apache.poi.ss.format.CellFormatType;
 import org.apache.poi.ss.usermodel.Cell;
 import org.apache.poi.ss.usermodel.DateUtil;
 import org.apache.poi.ss.usermodel.Row;
@@ -63,6 +64,7 @@ public BeanSheetReader(XceliteSheet sheet, Class<T> type) {
     this.type = type;
     ColumnsExtractor extractor = new ColumnsExtractor(type);
     extractor.extract();
+    extractor.extractJpa();
     columns = extractor.getColumns(); 
     anyColumn = extractor.getAnyColumn();    
     mapper = new ColumnsMapper(columns);
@@ -164,18 +166,41 @@ private void writeToAnyColumnField(Field field, T object, Cell cell, String colu
   @SuppressWarnings("unchecked")
   private void writeToField(Field field, T object, Cell cell, Col column) {
     try {   
-      Object cellValue = readValueFromCell(cell);      
+      Object cellValue = readValueFromCell(cell);
+      if(cellValue == null && (field.getType() == Boolean.class || field.getType() == boolean.class)) {
+    	  cellValue = Boolean.FALSE;
+      }
       if (cellValue != null) {
         if (column.getConverter() != null) {
           ColumnValueConverter<Object, ?> converter = (ColumnValueConverter<Object, ?>) column.getConverter()
               .newInstance();
           cellValue = converter.deserialize(cellValue);
         } else {
-          cellValue = convertToFieldType(cellValue, field.getType());
+          cellValue = convertToFieldType(cellValue, field.getType(), column);
         }
       }
-      field.setAccessible(true);
-      field.set(object, cellValue);
+      boolean annotationPresent = field.isAnnotationPresent(javax.persistence.ManyToOne.class);
+      if(!annotationPresent) {
+    	  field.setAccessible(true);
+    	  field.set(object, cellValue);
+      } else {
+		  Object instance = field.getType().newInstance();
+		  Field[] declaredFields = instance.getClass().getDeclaredFields();
+		  Field idField = null;
+		  for (Field f : declaredFields) {
+			if(f.isAnnotationPresent(javax.persistence.Id.class)) {
+				idField = f;
+				break;
+			}
+		  }
+		  if(idField == null) idField = declaredFields[0];
+		  // Set the id field in the instance
+		  idField.setAccessible(true);
+		  idField.set(instance, cellValue);
+		  // Set the object value
+		  field.setAccessible(true);
+		  field.set(object, instance);
+      }
     }
     catch (IllegalAccessException e) {
       throw new RuntimeException(e);
@@ -184,7 +209,7 @@ private void writeToField(Field field, T object, Cell cell, Col column) {
     }
   }
 
-  private Object convertToFieldType(Object cellValue, Class<?> fieldType) {
+  private Object convertToFieldType(Object cellValue, Class<?> fieldType, Col column) {
     String value = String.valueOf(cellValue);
     if (fieldType == Double.class || fieldType == double.class) {
       return Double.valueOf(value);
@@ -207,6 +232,9 @@ private Object convertToFieldType(Object cellValue, Class<?> fieldType) {
     if (fieldType == Date.class) {
       return DateUtil.getJavaDate(Double.valueOf(value));
     }
+    if(fieldType == Boolean.class || fieldType == boolean.class) {
+    	return Boolean.valueOf(value);
+    }
     return value;
   }
 

src/main/java/com/ebay/xcelite/styles/CellStyles.java

@@ -22,7 +22,8 @@
 
 public final class CellStyles {
 
-  private final String DEFAULT_DATE_FORMAT = "ddd mmm dd hh:mm:ss yyy";
+//  private final String DEFAULT_DATE_FORMAT = "ddd mmm dd hh:mm:ss yyy";
+  private final String DEFAULT_DATE_FORMAT = "dd/mm/yyyy hh:mm:ss";
 
   private final Workbook wb;
   private CellStyle boldStyle;

src/main/java/com/ebay/xcelite/writer/BeanSheetWriter.java

@@ -25,6 +25,7 @@
 import java.util.Set;
 
 import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.CellStyle;
 import org.reflections.ReflectionUtils;
 
 import com.ebay.xcelite.annotate.NoConverterClass;
@@ -46,6 +47,7 @@ public BeanSheetWriter(XceliteSheet sheet, Class<T> type) {
     super(sheet, true);
     ColumnsExtractor extractor = new ColumnsExtractor(type);
     extractor.extract();
+    extractor.extractJpa();
     columns = extractor.getColumns();
     anyColumn = extractor.getAnyColumn();
   }
@@ -119,8 +121,9 @@ private void writeToCell(Cell cell, Col col, Object fieldValueObj) {
     }
 
     if (col.getType() == Date.class) {
-      if (col.getDataFormat() == null) {
-        cell.setCellStyle(CellStylesBank.get(sheet.getNativeSheet().getWorkbook()).getDateStyle());
+     if (col.getDataFormat() == null) {
+        CellStyle dateStyle = CellStylesBank.get(sheet.getNativeSheet().getWorkbook()).getDateStyle();
+		cell.setCellStyle(dateStyle);
       }
     }
 

src/main/java/com/ebay/xcelite/writer/SheetWriterAbs.java

@@ -15,8 +15,11 @@
 */
 package com.ebay.xcelite.writer;
 
+import java.lang.reflect.Field;
 import java.util.Date;
 
+import javax.persistence.Entity;
+
 import org.apache.poi.ss.usermodel.Cell;
 
 import com.ebay.xcelite.sheet.XceliteSheet;
@@ -30,6 +33,7 @@
  */
 public abstract class SheetWriterAbs<T> implements SheetWriter<T> {
 
+  private static final int MAX_EXCEL_CELL_CARACTERS = 32767;
   protected XceliteSheet sheet;
   protected boolean writeHeader;
 
@@ -52,11 +56,65 @@ protected void writeToCell(Cell cell, Object fieldValueObj, Class<?> dataType) {
         || type == Short.class || type == short.class) {
       cell.setCellType(Cell.CELL_TYPE_NUMERIC);
       cell.setCellValue(Double.valueOf(fieldValueObj.toString()));
-    } else {
+    } else if (type == String.class) {
       cell.setCellType(Cell.CELL_TYPE_STRING);
-      cell.setCellValue(fieldValueObj.toString());
+      String cellValue = extractStringValue(fieldValueObj);
+      cell.setCellValue(cellValue);
+    } else {
+    	Entity entity = type.getAnnotation(javax.persistence.Entity.class);
+    	if(entity != null) {
+    		try {
+    			Field[] fields = type.getDeclaredFields();
+    			Field idField = getIdField(fields);
+    			Object value = null;
+    			// If no Id field
+    			if(idField == null && fields.length > 0) {
+    				// TODO : Maybe We should sorts field by name and pick the first one. So that the reverse operation can be easy.
+    				idField = fields[0]; // Pick a random field
+    			}
+    			try {
+					idField.setAccessible(true);
+					value = idField.get(fieldValueObj);
+				} catch (IllegalArgumentException e) {
+			      throw new RuntimeException(e);
+				} catch (IllegalAccessException e) {
+			      throw new RuntimeException(e);
+				}
+    			if(value == null) value = "NOREF";
+				cell.setCellType(Cell.CELL_TYPE_STRING);
+				cell.setCellValue(value.toString());
+			} catch (SecurityException e) {
+		      throw new RuntimeException(e);
+			}
+    	}
     }
   }
+
+  /**
+   * Extract the String value, and shrink it to fix excell string size.
+   * @param fieldValueObj
+   * @return
+   */
+  private String extractStringValue(Object fieldValueObj) {
+	String cellValue = fieldValueObj.toString();
+      if(cellValue == null) cellValue = "";
+      if(cellValue.length() > MAX_EXCEL_CELL_CARACTERS) {
+    	  cellValue = cellValue.substring(0, 32764);
+    	  cellValue += "...";
+      }
+	return cellValue;
+  }
+
+  private Field getIdField(Field[] fields) {
+	Field idField = null;
+	for (Field field : fields) {
+		if(field.getAnnotation(javax.persistence.Id.class) != null) {
+			idField = field;
+			break;
+		}
+	}
+	return idField;
+  }
 
   @Override
   public void generateHeaderRow(boolean generateHeaderRow) {