This filter pretty-prints field-oriented XML without mixed content. all added indentation and newlines will be passed on down the filter chain (if any).
In general, all whitespace in an XML document is potentially
significant, so a general-purpose XML writing tool like the
XMLWriter class cannot
add newlines or indentation.
There is, however, a large class of XML documents where information is strictly fielded: each element contains either character data or other elements, but not both. For this special case, it is possible for a writing tool to provide automatic indentation and newlines without requiring extra work from the user. Note that this class will likely not yield appropriate results for document-oriented XML like XHTML pages, which mix character data and elements together.
This writer will automatically place each start tag on a new line, optionally indented if an indent step is provided (by default, there is no indentation). If an element contains other elements, the end tag will also appear on a new line with leading indentation. Consider, for example, the following code:
DataWriter w = new DataWriter();
w.setIndentStep(2);
w.startDocument();
w.startElement("Person");
w.dataElement("name", "Jane Smith");
w.dataElement("date-of-birth", "1965-05-23");
w.dataElement("citizenship", "US");
w.endElement("Person");
w.endDocument();
This code will produce the following document:
<?xml version="1.0" standalone="yes"?>
<Person>
<name>Jane Smith</name>
<date-of-birth>1965-05-23</date-of-birth>
<citizenship>US</citizenship>
</Person>
This class inherits from XMLWriter,
and provides all of the same support for Namespaces.
XMLWriter
| Modifier and Type | Field and Description |
|---|---|
| private int | |
| private String | |
| private static final Object | |
| private static final Object | |
| private static final Object | |
| private Object | |
| private Stack |
| Access | Constructor and Description |
|---|---|
| public | DataWriter(Writer
The character stream where the XML document
will be written. writer, String If non-null string is specified, it is written as a part
of the XML declaration. encoding, CharacterEscapeHandler escape handler _escapeHandler)Create a new data writer for the specified output. |
| public | |
| public |
| Modifier and Type | Method and Description |
|---|---|
| public void | characters(char[]
The characters to write. ch, int The starting position in the array. start, int The number of characters to use. length)Overrides com. Implements org. Write a sequence of characters. |
| public void | comment(char[] ch, int start, int length)
Overrides com. Implements org. Report an XML comment anywhere in the document. |
| private void | |
| public void | endElement(String
The element's Namespace URI. uri, String The element's local name. localName, String The element's qualified (prefixed) name. qName)Overrides com. Implements org. Write an end tag. |
| public int | Returns: The number of spaces in each indentation step, or 0 or less for no indentation.
Deprecated
Only return the length of the indent string.
Return the current indent step. |
| public void | reset()
Overrides com. Reset the writer so that it can be reused. |
| public void | setIndentStep(int
The new indent step (0 or less for no
indentation). indentStep)
Deprecated
Should use the version that takes string.
Set the current indent step. |
| public void | |
| public void | startElement(String
The element's Namespace URI. uri, String The element's local name. localName, String The element's qualified (prefixed) name. qName, Attributes The element's attribute list. atts)Overrides com. Implements org. Write a start tag. |
| depth | back to summary |
|---|---|
| private int depth | |
| indentStep | back to summary |
|---|---|
| private String indentStep | |
| SEEN_DATA | back to summary |
|---|---|
| private static final Object SEEN_DATA | |
| SEEN_ELEMENT | back to summary |
|---|---|
| private static final Object SEEN_ELEMENT | |
| SEEN_NOTHING | back to summary |
|---|---|
| private static final Object SEEN_NOTHING | |
| state | back to summary |
|---|---|
| private Object state | |
| stateStack | back to summary |
|---|---|
| private Stack<Object> stateStack | |
| DataWriter | back to summary |
|---|---|
| public DataWriter(Writer writer, String encoding, CharacterEscapeHandler _escapeHandler) Create a new data writer for the specified output.
| |
| DataWriter | back to summary |
|---|---|
| public DataWriter(Writer writer, String encoding) | |
| DataWriter | back to summary |
|---|---|
| public DataWriter(Writer writer) | |
| characters | back to summary |
|---|---|
| public void characters(char[] ch, int start, int length) throws SAXException Overrides com. Implements org. Write a sequence of characters.
| |
| comment | back to summary |
|---|---|
| public void comment(char[] ch, int start, int length) throws SAXException Overrides com. Implements org. Doc from org. Report an XML comment anywhere in the document. This callback will be used for comments inside or outside the document element, including comments in the external DTD subset (if read). Comments in the DTD must be properly nested inside start/endDTD and start/endEntity events (if used).
| |
| doIndent | back to summary |
|---|---|
| private void doIndent() throws SAXException Print indentation for the current level.
| |
| endElement | back to summary |
|---|---|
| public void endElement(String uri, String localName, String qName) throws SAXException Overrides com. Implements org. Write an end tag. If the element has contained other elements, the tag will appear indented on a new line; otherwise, it will appear immediately following whatever came before. The newline and indentation will be passed on down the filter chain through regular characters events.
| |
| getIndentStep | back to summary |
|---|---|
| public int getIndentStep()
Deprecated Only return the length of the indent string. Return the current indent step. Return the current indent step: each start tag will be indented by this number of spaces times the number of ancestors that the element has.
| |
| reset | back to summary |
|---|---|
| public void reset() Overrides com. Reset the writer so that it can be reused. This method is especially useful if the writer failed with an exception the last time through.
| |
| setIndentStep | back to summary |
|---|---|
| public void setIndentStep(int indentStep)
Deprecated Should use the version that takes string. Set the current indent step.
| |
| setIndentStep | back to summary |
|---|---|
| public void setIndentStep(String s) | |
| startElement | back to summary |
|---|---|
| public void startElement(String uri, String localName, String qName, Attributes atts) throws SAXException Overrides com. Implements org. Write a start tag. Each tag will begin on a new line, and will be indented by the current indent step times the number of ancestors that the element has. The newline and indentation will be passed on down the filter chain through regular characters events.
| |