NodeParser (DB Exporter (and Importer) 1.5.2 API)

```
public interface NodeParser
```
Represents a node in streaming XML documents. This is a small abstraction layer over StAX that allows other streaming data formats to be used (JSON, ASN.1, ?) and make it easier to deal with StAX, of which the API can be a bit tedious. This interface also provides type conversion instead of just strings. This interface only provides read access to a streaming node graph.

Author:

Erik van Zijst

See Also:

counterpart of this interface that provides the ability to write node graphs., NodeStreamReader

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`String`	`getAttribute(String key)` Retrieves the value of an attribute of the current node.
`void`	`getContent(Writer writer)` Similar to `getContentAsString()`, but writes the contents to the specified `Writer` instance.
`BigDecimal`	`getContentAsBigDecimal()`
`BigInteger`	`getContentAsBigInteger()` Similar to `getContentAsString()`, but converts content to a `BigInteger` instance.
`Boolean`	`getContentAsBoolean()` Similar to `getContentAsString()`, but converts content to a boolean value.
`Date`	`getContentAsDate()` Similar to `getContentAsString()`, but converts content to a `Date` instance.
`String`	`getContentAsString()` Returns the content of the current node as a string.
`String`	`getName()` Returns the name of the current entity.
`NodeParser`	`getNextNode()` Returns the next node in the graph.
`String`	`getRequiredAttribute(String key)` Retrieves the value of an attribute of the current node.
`boolean`	`isClosed()` Returns `true` if this instance represents the end of a node (closing tag in XML).

- Method Detail
  - getAttribute
```
String getAttribute(String key)
             throws IllegalStateException
```
    Retrieves the value of an attribute of the current node. If the attribute does not exist, null is returned.
    
    Parameters:
    
    key - the name of the attribute.
    
    Returns:
    
    the value of the attribute, or null if the attribute does not exist.
    
    Throws:
    
    ImportExportException - when the input could not be parsed.
    
    IllegalStateException - when this method was called after one of the getContent..., or the getNextNode() method was called.
  - getRequiredAttribute
```
String getRequiredAttribute(String key)
                     throws IllegalStateException
```
    Retrieves the value of an attribute of the current node. If the attribute does not exist, a ImportExportException is thrown.
    
    Parameters:
    
    key - the name of the attribute.
    
    Returns:
    
    the value of the attribute (can be an empty string, or even null if the attribute is present, but has no value - think xsi:nil="true").
    
    Throws:
    
    ImportExportException - when the input could not be parsed.
    
    IllegalStateException - when this method was called after one of the getContent..., or the getNextNode() method was called.
  - getName
```
String getName()
```
    Returns the name of the current entity.
    
    Returns:
    
    the name of the current entity.
    
    Throws:
    
    ImportExportException - when the input could not be parsed.
  - isClosed
```
boolean isClosed()
```
    Returns true if this instance represents the end of a node (closing tag in XML). If this is the case, getNextNode() will return a reference to the parent node. Also, when the end of a node is reached, getAttribute(String), getRequiredAttribute(String) and the various getContent() methods can no longer be invoked. Doing so will raise a ImportExportException.
    
    Returns:
    
    true if this instance represents the end of a node.
    
    Throws:
    
    ImportExportException - when the input could not be parsed.
  - getNextNode
```
NodeParser getNextNode()
```
    Returns the next node in the graph. This could be:
  - a child node (in which case isClosed() will be false on the returned instance);
  - the close tag of the current node (isClosed() will be true on the returned instance;
  - the end of the document (isClosed() is true on the current instance), then null will be returned.

Returns:: the next node in the graph.
Throws:: ImportExportException - when the input could not be parsed.

getContentAsString
```
String getContentAsString()
                   throws IllegalStateException
```
Returns the content of the current node as a string. A node either contains content, child nodes, or nothing at all. If the current node does not contain content, a ImportExportException is thrown. When the current node is a content node, but contains no data (e.g. in XML), null is returned.
When this method returns, the current node will be closed. Calling this method again will raise an IllegalStateException.

Returns:

the content of the current node.

Throws:

ImportExportException - when the current node is not a content node, or when the input could not be parsed.

IllegalStateException - if the current node cannot contain content (for instance because isClosed() is true.

getContentAsBoolean
```
Boolean getContentAsBoolean()
                     throws IllegalStateException
```
Similar to getContentAsString(), but converts content to a boolean value.

Returns:

the content of the current node as a boolean value.

Throws:

IllegalStateException - if the current node cannot contain content (for instance because isClosed() is true.

getContentAsDate
```
Date getContentAsDate()
               throws IllegalStateException
```
Similar to getContentAsString(), but converts content to a Date instance.

Returns:

the content of the current node as a Date instance.

Throws:

ImportExportException - when the current node is not a content node, or when the input could not be parsed, or when the content does not conform to the standardized date format.

IllegalStateException - if the current node cannot contain content (for instance because isClosed() is true.

getContentAsBigInteger
```
BigInteger getContentAsBigInteger()
                           throws IllegalStateException
```
Similar to getContentAsString(), but converts content to a BigInteger instance.

Returns:

the content of the current node as a BigInteger instance.

Throws:

ImportExportException - when the current node is not a content node, or when the input could not be parsed, or the content does not contain a numeric integer value.

IllegalStateException - if the current node cannot contain content (for instance because isClosed() is true.

getContentAsBigDecimal

BigDecimal getContentAsBigDecimal()
                           throws IllegalStateException

Throws:: IllegalStateException

getContent
```
void getContent(Writer writer)
         throws IllegalStateException
```
Similar to getContentAsString(), but writes the contents to the specified Writer instance. Useful for reading large lumps of content in a memory-efficient way. The writer is not closed.

Parameters:

writer -

Throws:

ImportExportException - when the current node is not a content node, or when the input could not be parsed.

IllegalStateException - if the current node cannot contain content (for instance because isClosed() is true.

Interface NodeParser

Method Summary

Method Detail

getAttribute

getRequiredAttribute

getName

isClosed

getNextNode

getContentAsString

getContentAsBoolean

getContentAsDate

getContentAsBigInteger

getContentAsBigDecimal

getContent