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基于Java实现DBase DBF文件的解析和显示

JDK19编译运行，实现了数据库字段和数据解析显示。

首先解析数据库文件头代码

		byte bytes[] = Files.readAllBytes(Paths.get(file));BinaryBufferArray bis = new BinaryBufferArray(bytes);DBF dbf = new DBF();dbf.VersionNumber = bis.ReadUInt8();		// 版本号dbf.DateOfLastUpdate = bis.ReadBytes(3);  	// 最后更新日期dbf.NumberOfRecords = bis.ReadUInt32();		// 记录数量dbf.LengthOfHeaderStructure = bis.ReadUInt16();	// 文件头长（内容开始位置）dbf.LengthOfEachRecord  = bis.ReadUInt16();	// 每条记录长度short Reserved = bis.ReadInt16();dbf.IncompleteTransac = bis.ReadUInt8();	dbf.EncryptionFlag = bis.ReadUInt8();dbf.FreeRecordThread = bis.ReadInt32();long ReservedForMultiUser= bis.ReadInt64();dbf.MDXFlag = bis.ReadUInt8();dbf.LanguageDriver = bis.ReadUInt8();	Reserved = bis.ReadInt16();

解析字段代码

		dbf.fields = new Vector<Field>();while (true) {byte _b = bis.ReadInt8();if (_b == 0x0d) 	// 是否结束break ;byte[] bs = bis.ReadInt8(31);byte[] all = new byte[32];all[0] = _b;System.arraycopy(bs, 0, all, 1, 31);Field field = Field.parse(all);	dbf.fields.add(field);}

	static Field parse(byte[] b) throws IOException  {Field field = new Field();BinaryBufferArray t = new BinaryBufferArray(b);field.name = t.ReadAsciiString(11).trim();	//字段名称field.type = t.ReadAsciiChar();				// 字段类型t.SkipBytes(4);field.length = t.ReadUInt8();				// 字段长度field.precision = t.ReadUInt8();			// 精度t.SkipBytes(2);field.id = t.ReadUInt8();t.SkipBytes(10);field.mdx = t.ReadUInt8();return field;}

解析数据代码：

		dbf.resultset = new Vector<Map<String, Object>>();	//结果集for (int i=0; i<dbf.NumberOfRecords-1; i++) {char delete = '\0';		delete = bis.ReadAsciiChar();	// 读入删除标记HashMap<String,Object> map = new HashMap<>();for (int j=0; j<dbf.fields.size(); j++) {Field field = dbf.fields.get(j);char type = field.getType();int len = field.getLength();Object val = null;byte[] b = bis.ReadBytes(len);	//读取字段值if (field.getType() == 'N')val = new String(b);else if (field.getType() =='C')val = new String(b, "UTF-8");map.put(field.getName(), val);}map.put("delete", delete);dbf.resultset.add(map);}

读入dbf文件，解析显示如下：