1.12 version commit. Added ability for cloning DBF file.

Author: galisha

CHANGELOG.md

@@ -3,6 +3,7 @@ Version history
 
 |Date      | Ver | Author                      | Description        |
 |----------|-----|-----------------------------|--------------------|
+|2021-04-25| 1.12| galisha.                    | Added ability for cloning DBF file. |
 |2020-08-31| 1.11| galisha.                    | Added ability of append records to existed DBF file. |
 |2020-01-08| 1.10| frankvdh, galisha.          | Fixed two issues: 1) Column names not upper case 2) Buffer reads are not stream-safe |
 |2019-07-10| 1.09| galisha.                    | Added handling for such bad numeric as: 1219,.0000 |

README.md

@@ -1,6 +1,6 @@
 # DbfEngine Java API
 
-DbfEngine - a Java API to read, write and append xBase(DBASE, Foxpro dbf files). Also API allows read memory files (.mem) of Foxpro.
+DbfEngine - a Java API to read, write, append and clone xBase(DBASE, Foxpro dbf files). Also API allows read memory files (.mem) of Foxpro.
 Samples for both operations you can see at [DbfEngine javadoc](https://smart-flex.ru/htm/de_api/index.html)
 
 This API is pure lightweight library without memory consumption and any third party libraries (there are no java loggers and etc.)
@@ -81,7 +81,60 @@ public class Fp26Writer {
         Fp26Writer.testWrite();
     }
 }
+
+public class DbfClonePerformance {
+
+	private static void cloneDBF(String srcFile, String cloneFile) {
+		File room64File = new File(srcFile);
+		System.out.println("Length src file (bytes): " + room64File.length() + " (megabytes): " + room64File.length()/(1024*1024));
+		DbfHeader header = DbfEngine.getHeader(room64File, "Cp866");
+		System.out.println(header.toString());
+		DbfIterator dbfIterator = header.getDbfIterator();
+
+		File cloneDbf = new File(cloneFile);
+		if (cloneDbf.exists()) {
+			cloneDbf.delete();
+		}
+		DbfAppender dbfAppender = DbfEngine.getWriter(cloneDbf,
+				DbfCodePages.Cp866);
+		dbfAppender.defineColumns(header);
+
+		while (dbfIterator.hasMoreRecords()) {
+			DbfRecord dbfRecord = dbfIterator.nextRecord();
+
+			// here can be your filtering code ....
+			
+			DbfStatement statement = dbfAppender.getStatement();
+			statement.fillStatement(dbfRecord);
+			statement.insertStatement();
+		}
+
+		dbfAppender.writeDbfAndClose();
+		header.closeDbfHeader();
+	}
+
+	public static void main(String[] args) {
+
+		long start = System.currentTimeMillis();
+		
+		cloneDBF("F:\\fias_dbf\\ROOM64.DBF",
+				"F:\\fias_dbf\\ROOM64_CLONE.DBF");
+
+		long finish = System.currentTimeMillis();
+		
+		System.out.println("Clone finished for: " + (finish - start)/1000 + " sec");
+	}
+}
 ```
+#### Performance
+
+The result of performance are (below is the work log of DbfClonePerformance class):
+
+* Length src file (bytes): 600606501 (megabytes): 572
+* DbfHeader [firstRecordPosition=641, countRecords=1078287, countColumns=19, lengthRecord=557, codePage=Cp866, typeDbf={3,FoxBASE_dBASE_III_PLUS_without_memo}]
+* Clone finished for: 52 sec
+
+This java code is worked under jdk1.6/32; Intel Core i3; Windows 10. And there is no one messages such as: java.lang.OutOfMemoryError: Java heap space
 
 #### Licensing
 

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>ru.smartflex.tools.dbf</groupId>
     <artifactId>DbfEngine</artifactId>
-    <version>1.11</version>
+    <version>1.12</version>
     <name>DbfEngine - a small Java library to read, write, append xBase(DBASE, Foxpro dbf/mem files)</name>
 
     <properties>

src/main/java/ru/smartflex/tools/dbf/DbfAppender.java

@@ -100,6 +100,25 @@ public void defineColumns(DbfColumn... dbfColumns) {
         }
     }
 
+    /**
+     * Defines columns for dbf file based on source header of dbf file.
+     * @param header source header of dbf file
+     * @since 1.12
+     */
+    public void defineColumns(DbfHeader header) {
+        if (flagAppendExistedFile) {
+            throw new DbfEngineException(DbfConstants.EXCP_DEF_COLS_NOT_ALLOWED);
+        }
+        if (header.getOrderedColumnList().size() == 0) {
+            throw new DbfEngineException(DbfConstants.EXCP_COLUMN_ADD);
+        }
+        dbfHeader = new DbfHeader();
+
+        for (DbfColumn dc : header.getOrderedColumnList()) {
+            dbfHeader.addColumn(dc);
+        }
+    }
+
     /**
      * Writes records into dbf file and then closes it.
      *

src/main/java/ru/smartflex/tools/dbf/DbfRecord.java

@@ -346,4 +346,13 @@ public String getAsString(DbfColumn column) {
     public int getCurrentRecord() {
         return currentRecord;
     }
+
+    /**
+     * Return record
+     * @return current record as byte array
+     * @since 1.12
+     */
+    byte[] getRecord() {
+        return record;
+    }
 }

src/main/java/ru/smartflex/tools/dbf/DbfStatement.java

@@ -247,4 +247,8 @@ private DbfColumnPosition definePosition(String colName, DbfColumnTypes dct) {
         return dbfColumnPos;
     }
 
+    public void fillStatement(DbfRecord dbfRecord) {
+        System.arraycopy(dbfRecord.getRecord(), 0, rec, 0, rec.length);
+    }
+
 }

src/test/java/ru/smartflex/tools/dbf/DbfWriterTest.java

@@ -7,6 +7,7 @@
 import java.io.File;
 import java.math.BigDecimal;
 import java.util.Date;
+import java.util.Iterator;
 
 import static org.junit.Assert.assertEquals;
 
@@ -89,6 +90,38 @@ public void testAppendDbf() {
         writeDbf.delete();
     }
 
+    @Test
+    public void testDbfCloning() {
+
+        DbfHeader dbfHeader = DbfEngine.getHeader(
+                TestHelper.getFile("FP_26_SAMPLE.DBF"), null);
+        DbfIterator dbfIterator = dbfHeader.getDbfIterator();
+        System.out.println("DBF header info: " + dbfHeader.toString());
+
+        Iterator<DbfColumn> iter = dbfHeader.getColumnIterator();
+        while (iter.hasNext()) {
+            DbfColumn column = iter.next();
+            System.out.println(column.getColumnName() + " " + column.getDbfColumnType() + " " + column.getDbfColumnPosition().getColumnLength());
+        }
+
+        File cloneDbf = new File("FP_26_SAMPLE_CLONE.DBF");
+        if (cloneDbf.exists()) {
+            cloneDbf.delete();
+        }
+        DbfAppender dbfAppender = DbfEngine.getWriter(cloneDbf, DbfCodePages.Cp866);
+        dbfAppender.defineColumns(dbfHeader);
+
+        while (dbfIterator.hasMoreRecords()) {
+            DbfRecord dbfRecord = dbfIterator.nextRecord();
+            DbfStatement statement = dbfAppender.getStatement();
+            statement.fillStatement(dbfRecord);
+            statement.insertStatement();
+        }
+
+        dbfAppender.writeDbfAndClose();
+        dbfHeader.closeDbfHeader();
+    }
+
     private void writeTwoRecordsToDbf(File writeDbf) {
 
         DbfAppender dbfAppender = DbfEngine.getWriter(writeDbf, DbfCodePages.Cp866);