Geotools modifying Shapefile property name garbled problem

The discussion address for the GeoServer Chinese community is:http://opengeo.cn/bbs/read.php?tid=1701&page=e& #a

After modifying shapefiles with Geotools, the property names in the DBF file contents are garbled, but the property values are not garbled. The changes have not been garbled before.
And the code has been coded in the following way:

Shapefiledatastore shape = new Shapefiledatastore (URL), Shape.setstringcharset (Charset.forname ("GBK"));

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My modified code is as follows:

    /** * Modify Shapefiles. * @param dataStore * @param fidstr the data to be modified corresponds to Featureid * @return */public static Boolean Updateshapefile (Sh          Apefiledatastore datastore,string fidstr) {defaulttransaction transaction = null;          Simplefeaturestore store = null;            try {datastore.setstringcharset (charset.forname ("GBK"));            string[] Featurenames = Datastore.gettypenames ();              String featurename = featurenames[0];                        Creates the default transaction object transaction = new Defaulttransaction ();              Also indicate the feature name used by the data source, usually the Shapefile file name and the Shapefile type name are usually the same.            store = (simplefeaturestore) datastore.getfeaturesource (featurename);            Associate default transaction and data source Store.settransaction (transaction);            Create filter FilterFactory2 FF = (FilterFactory2) commonfactoryfinder.getfilterfactory2 (null);            Set<featureid> fids = new hashset<featureid> (); Featureid FID =Ff.featureid (FIDSTR);            Fids.add (FID);            Filter filter = (filter) ff.id (FIDS);                        Modify the filtered feature according to the filter store.modifyfeatures ("Table number", "Test", filter);          Submit Transaction.commit ();             } catch (IOException e) {e.printstacktrace ();              try {//rollback transaction.rollback ();              } catch (IOException E1) {e1.printstacktrace ();        } return false;                  }finally{if (transaction!=null) {//Off transaction.close ();            transaction = NULL;    }} return true; }

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After locating the problem is found in transaction.commit ();

and the file contents of SHP files also have Chinese characters, but there is no garbled problem, then from the dbf file header.

View the source code of the Geotools, found that the operation of the DBF file is under the ORG\GEOTOOLS\DATA\SHAPEFILE\DBF package, where the class Dbasefilewriter implementation of the DBF file write operations, Includes the write of the property name (head) and the write of the property value (body), while the head is written in the

    Public Dbasefilewriter (Dbasefileheader header, Writablebytechannel out, Charset Charset)            throws IOException {        Write the header        Header.writeheader (out);    }

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The Writeheader method is defined in the Dbasefileheader class.

The original code is as follows:

              Write the field name for              (int j = 0; J < one; J + +) {                  if (Fields.fieldName.length () > J) {                      buffer.put ( BYTE) fields.fieldName.charAt (j));                  else {                      buffer.put ((byte) 0);                  }              }

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This means that the attribute name is placed in buffer as a byte, a property name cannot be more than 11 bytes, and less than 11 is supplemented with (byte) 0.
The key is (byte) fields.fieldName.charAt (j), which takes two bytes for Chinese characters, except for the problem when it is converted from char to byte.
Take the following string:
String str = "capital";
byte[] bytes = Str.getbytes ();
for (int i=0;i<bytes.length;i++)
System.out.println (bytes);
The output should be:
-41
-54
This takes up two bytes, which is the right one.
If you follow the method in it:
char chars = ' capital ';
byte[] bytes = {(byte) chars};
for (int i=0;i<bytes.length;i++)
System.out.println (bytes);
The output is:
68
It's obviously not right here.

Just follow the above logic, modify the original code as follows (I'm just a method here, this code should be optimized again):
int j = 0;
for (int counter=0; j<11&&counter<fields.fieldname.length (); counter++) {
Char cha = fields.fieldName.charAt (counter);
String str = new String (cha+ "");
byte[] bytes = Str.getbytes ();
for (int k=0;k<bytes.length;k++) {
Buffer.put (Bytes[k]);
j + +;
}
}
if (j!=11) {
for (int k=0;k< (11-J); k++) {
Buffer.put ((byte) 0);
}
}

Geotools modifying Shapefile property name garbled problem