我有一组要转换为
XML的CSV数据.代码看起来不错,但输出不够完美.它省略了一些列,因为它们没有值,并且产生了很长的XML数据而不是破坏它.
这是我的CSV数据示例：
Name Age Sex
chi 23
kay 19 male
John male
我的代码：
public class XMLCreators {
// Protected Properties
protected DocumentBuilderFactory domFactory = null;
protected DocumentBuilder domBuilder = null;
public XMLCreators() {
try {
domFactory = DocumentBuilderFactory.newInstance();
domBuilder = domFactory.newDocumentBuilder();
} catch (FactoryConfigurationError exp) {
System.err.println(exp.toString());
} catch (ParserConfigurationException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
}
public int convertFile(String csvFileName, String xmlFileName,
String delimiter) {
int rowsCount = -1;
try {
Document newDoc = domBuilder.newDocument();
// Root element
Element rootElement = newDoc.createElement("XMLCreators");
newDoc.appendChild(rootElement);
// Read csv file
BufferedReader csvReader;
csvReader = new BufferedReader(new FileReader(csvFileName));
int fieldCount = 0;
String[] csvFields = null;
StringTokenizer stringTokenizer = null;
// Assumes the first line in CSV file is column/field names
// The column names are used to name the elements in the XML file,
// avoid the use of Space or other characters not suitable for XML element
// naming
String curLine = csvReader.readLine();
if (curLine != null) {
// how about other form of csv files?
stringTokenizer = new StringTokenizer(curLine, delimiter);
fieldCount = stringTokenizer.countTokens();
if (fieldCount > 0) {
csvFields = new String[fieldCount];
int i = 0;
while (stringTokenizer.hasMoreElements())
csvFields[i++] = String.valueOf(stringTokenizer.nextElement());
}
}
// At this point the coulmns are known, now read data by lines
while ((curLine = csvReader.readLine()) != null) {
stringTokenizer = new StringTokenizer(curLine, delimiter);
fieldCount = stringTokenizer.countTokens();
if (fieldCount > 0) {
Element rowElement = newDoc.createElement("row");
int i = 0;
while (stringTokenizer.hasMoreElements()) {
try {
String curValue = String.valueOf(stringTokenizer.nextElement());
Element curElement = newDoc.createElement(csvFields[i++]);
curElement.appendChild(newDoc.createTextNode(curValue));
rowElement.appendChild(curElement);
} catch (Exception exp) {
}
}
rootElement.appendChild(rowElement);
rowsCount++;
}
}
csvReader.close();
// Save the document to the disk file
TransformerFactory tranFactory = TransformerFactory.newInstance();
Transformer aTransformer = tranFactory.newTransformer();
Source src = new DOMSource(newDoc);
Result result = new StreamResult(new File(xmlFileName));
aTransformer.transform(src, result);
rowsCount++;
// Output to console for testing
// Resultt result = new StreamResult(System.out);
} catch (IOException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
return rowsCount;
// "XLM Document has been created" + rowsCount;
}
}
当对上述数据执行此代码时,它会产生：
<?xml version="1.0" encoding="UTF-8"?>
<XMLCreators>
<row>
<Name>chi</Name>
<Age>23</Age>
</row>
<row>
<Name>kay</Name>
<Age>19</Age>
<sex>male</sex>
</row>
<row>
<Name>john</Name>
<Age>male</Age>
</row>
</XMLCreators>
我自己以这种形式安排了它,但输出产生了很长的路线.要生成的输出应该是：
<?xml version="1.0" encoding="UTF-8"?>
<XMLCreators>
<row>
<Name>chi</Name>
<Age>23</Age>
<sex></sex>
</row>
<row>
<Name>kay</Name>
<Age>19</Age>
<sex>male</sex>
</row>
<row>
<Name>john</Name>
<Age></Age>
<sex>male</sex>
</row>
</XMLCreators>
最佳答案 我同意肯尼特的观点.
我只是补充道
aTransformer .setOutputProperty(OutputKeys.INDENT, "yes");
aTransformer .setOutputProperty(OutputKeys.METHOD, "xml");
aTransformer .setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
这在元素之间添加了一条新行并允许缩进.
更新
让我们从这样一个事实开始,即您呈现的文件不是CSV(逗号分隔值)文件,我会让您担心这个问题……
List<String> headers = new ArrayList<String>(5);
File file = new File("Names2.csv");
BufferedReader reader = null;
try {
DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder domBuilder = domFactory.newDocumentBuilder();
Document newDoc = domBuilder.newDocument();
// Root element
Element rootElement = newDoc.createElement("XMLCreators");
newDoc.appendChild(rootElement);
reader = new BufferedReader(new FileReader(file));
int line = 0;
String text = null;
while ((text = reader.readLine()) != null) {
StringTokenizer st = new StringTokenizer(text, " ", false);
String[] rowValues = new String[st.countTokens()];
int index = 0;
while (st.hasMoreTokens()) {
String next = st.nextToken();
rowValues[index++] = next;
}
//String[] rowValues = text.split(",");
if (line == 0) { // Header row
for (String col : rowValues) {
headers.add(col);
}
} else { // Data row
Element rowElement = newDoc.createElement("row");
rootElement.appendChild(rowElement);
for (int col = 0; col < headers.size(); col++) {
String header = headers.get(col);
String value = null;
if (col < rowValues.length) {
value = rowValues[col];
} else {
// ?? Default value
value = "";
}
Element curElement = newDoc.createElement(header);
curElement.appendChild(newDoc.createTextNode(value));
rowElement.appendChild(curElement);
}
}
line++;
}
ByteArrayOutputStream baos = null;
OutputStreamWriter osw = null;
try {
baos = new ByteArrayOutputStream();
osw = new OutputStreamWriter(baos);
TransformerFactory tranFactory = TransformerFactory.newInstance();
Transformer aTransformer = tranFactory.newTransformer();
aTransformer.setOutputProperty(OutputKeys.INDENT, "yes");
aTransformer.setOutputProperty(OutputKeys.METHOD, "xml");
aTransformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
Source src = new DOMSource(newDoc);
Result result = new StreamResult(osw);
aTransformer.transform(src, result);
osw.flush();
System.out.println(new String(baos.toByteArray()));
} catch (Exception exp) {
exp.printStackTrace();
} finally {
try {
osw.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
}
} catch (Exception e) {
e.printStackTrace();
}
现在我在这里使用了List而不是Map.您需要决定如何最好地解决缺失值问题.事先不知道文件的结构,这不是一个简单的解决方案.
无论如何,我最终得到了
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<XMLCreators>
<row>
<Name>chi</Name>
<Age>23</Age>
<Sex/>
</row>
<row>
<Name>kay</Name>
<Age>19</Age>
<Sex>male</Sex>
</row>
<row>
<Name>John</Name>
<Age>male</Age>
<Sex/>
</row>
</XMLCreators>
更新合并
public class XMLCreators {
// Protected Properties
protected DocumentBuilderFactory domFactory = null;
protected DocumentBuilder domBuilder = null;
public XMLCreators() {
try {
domFactory = DocumentBuilderFactory.newInstance();
domBuilder = domFactory.newDocumentBuilder();
} catch (FactoryConfigurationError exp) {
System.err.println(exp.toString());
} catch (ParserConfigurationException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
}
public int convertFile(String csvFileName, String xmlFileName,
String delimiter) {
int rowsCount = -1;
try {
Document newDoc = domBuilder.newDocument();
// Root element
Element rootElement = newDoc.createElement("XMLCreators");
newDoc.appendChild(rootElement);
// Read csv file
BufferedReader csvReader;
csvReader = new BufferedReader(new FileReader(csvFileName));
// int fieldCount = 0;
// String[] csvFields = null;
// StringTokenizer stringTokenizer = null;
//
// // Assumes the first line in CSV file is column/field names
// // The column names are used to name the elements in the XML file,
// // avoid the use of Space or other characters not suitable for XML element
// // naming
//
// String curLine = csvReader.readLine();
// if (curLine != null) {
// // how about other form of csv files?
// stringTokenizer = new StringTokenizer(curLine, delimiter);
// fieldCount = stringTokenizer.countTokens();
// if (fieldCount > 0) {
// csvFields = new String[fieldCount];
// int i = 0;
// while (stringTokenizer.hasMoreElements()) {
// csvFields[i++] = String.valueOf(stringTokenizer.nextElement());
// }
// }
// }
//
// // At this point the coulmns are known, now read data by lines
// while ((curLine = csvReader.readLine()) != null) {
// stringTokenizer = new StringTokenizer(curLine, delimiter);
// fieldCount = stringTokenizer.countTokens();
// if (fieldCount > 0) {
// Element rowElement = newDoc.createElement("row");
// int i = 0;
// while (stringTokenizer.hasMoreElements()) {
// try {
// String curValue = String.valueOf(stringTokenizer.nextElement());
// Element curElement = newDoc.createElement(csvFields[i++]);
// curElement.appendChild(newDoc.createTextNode(curValue));
// rowElement.appendChild(curElement);
// } catch (Exception exp) {
// }
// }
// rootElement.appendChild(rowElement);
// rowsCount++;
// }
// }
// csvReader.close();
//
// // Save the document to the disk file
// TransformerFactory tranFactory = TransformerFactory.newInstance();
// Transformer aTransformer = tranFactory.newTransformer();
// Source src = new DOMSource(newDoc);
// Result result = new StreamResult(new File(xmlFileName));
// aTransformer.transform(src, result);
// rowsCount++;
int line = 0;
List<String> headers = new ArrayList<String>(5);
String text = null;
while ((text = csvReader.readLine()) != null) {
StringTokenizer st = new StringTokenizer(text, delimiter, false);
String[] rowValues = new String[st.countTokens()];
int index = 0;
while (st.hasMoreTokens()) {
String next = st.nextToken();
rowValues[index++] = next;
}
if (line == 0) { // Header row
for (String col : rowValues) {
headers.add(col);
}
} else { // Data row
rowsCount++;
Element rowElement = newDoc.createElement("row");
rootElement.appendChild(rowElement);
for (int col = 0; col < headers.size(); col++) {
String header = headers.get(col);
String value = null;
if (col < rowValues.length) {
value = rowValues[col];
} else {
// ?? Default value
value = "";
}
Element curElement = newDoc.createElement(header);
curElement.appendChild(newDoc.createTextNode(value));
rowElement.appendChild(curElement);
}
}
line++;
}
ByteArrayOutputStream baos = null;
OutputStreamWriter osw = null;
try {
baos = new ByteArrayOutputStream();
osw = new OutputStreamWriter(baos);
TransformerFactory tranFactory = TransformerFactory.newInstance();
Transformer aTransformer = tranFactory.newTransformer();
aTransformer.setOutputProperty(OutputKeys.INDENT, "yes");
aTransformer.setOutputProperty(OutputKeys.METHOD, "xml");
aTransformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
Source src = new DOMSource(newDoc);
Result result = new StreamResult(osw);
aTransformer.transform(src, result);
osw.flush();
System.out.println(new String(baos.toByteArray()));
} catch (Exception exp) {
exp.printStackTrace();
} finally {
try {
osw.close();
} catch (Exception e) {
}
try {
baos.close();
} catch (Exception e) {
}
}
// Output to console for testing
// Resultt result = new StreamResult(System.out);
} catch (IOException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
return rowsCount;
// "XLM Document has been created" + rowsCount;
}
}
使用OpenCSV更新
public class XMLCreators {
// Protected Properties
protected DocumentBuilderFactory domFactory = null;
protected DocumentBuilder domBuilder = null;
public XMLCreators() {
try {
domFactory = DocumentBuilderFactory.newInstance();
domBuilder = domFactory.newDocumentBuilder();
} catch (FactoryConfigurationError exp) {
System.err.println(exp.toString());
} catch (ParserConfigurationException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
}
public int convertFile(String csvFileName, String xmlFileName,
String delimiter) {
int rowsCount = -1;
BufferedReader csvReader;
try {
Document newDoc = domBuilder.newDocument();
// Root element
Element rootElement = newDoc.createElement("XMLCreators");
newDoc.appendChild(rootElement);
// Read csv file
csvReader = new BufferedReader(new FileReader(csvFileName));
//** Now using the OpenCSV **//
CSVReader reader = new CSVReader(new FileReader("names.csv"), delimiter.charAt(0));
//CSVReader reader = new CSVReader(csvReader);
String[] nextLine;
int line = 0;
List<String> headers = new ArrayList<String>(5);
while ((nextLine = reader.readNext()) != null) {
if (line == 0) { // Header row
for (String col : nextLine) {
headers.add(col);
}
} else { // Data row
Element rowElement = newDoc.createElement("row");
rootElement.appendChild(rowElement);
int col = 0;
for (String value : nextLine) {
String header = headers.get(col);
Element curElement = newDoc.createElement(header);
curElement.appendChild(newDoc.createTextNode(value.trim()));
rowElement.appendChild(curElement);
col++;
}
}
line++;
}
//** End of CSV parsing**//
FileWriter writer = null;
try {
writer = new FileWriter(new File(xmlFileName));
TransformerFactory tranFactory = TransformerFactory.newInstance();
Transformer aTransformer = tranFactory.newTransformer();
aTransformer.setOutputProperty(OutputKeys.INDENT, "yes");
aTransformer.setOutputProperty(OutputKeys.METHOD, "xml");
aTransformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
Source src = new DOMSource(newDoc);
Result result = new StreamResult(writer);
aTransformer.transform(src, result);
writer.flush();
} catch (Exception exp) {
exp.printStackTrace();
} finally {
try {
writer.close();
} catch (Exception e) {
}
}
// Output to console for testing
// Resultt result = new StreamResult(System.out);
} catch (IOException exp) {
System.err.println(exp.toString());
} catch (Exception exp) {
System.err.println(exp.toString());
}
return rowsCount;
// "XLM Document has been created" + rowsCount;
}
}
