All Superinterfaces:

Inspectable

All Known Implementing Classes:

Value, Value.ArrayValue, Value.BoolValue, Value.DataValue, Value.DoubleValue, Value.EmptyValue, Value.LongValue, Value.ObjectValue, Value.StringValue
```
public interface Inspector
extends Inspectable
```
This is a generic API for accessing structured, generic, schemaless data. An inspector is a handle to a value that has one of 8 specific types: EMPTY, the 5 scalar types BOOL, LONG, DOUBLE, STRING, or DATA, the simple list-like ARRAY container and the struct-like OBJECT container. Instrospection methods are available, but you can also use accessors with a default value if you expect a certain type and just want your default value if some field doesn't exist or was of the wrong type.

Author:

havardpe

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`asBool()`	Access the inspector's value if it's a BOOLEAN; otherwise throws exception
`boolean`	`asBool(boolean defaultValue)`	Get the inspector's value (or the supplied default), never throws
`byte[]`	`asData()`	Access the inspector's value if it's DATA; otherwise throws exception
`byte[]`	`asData(byte[] defaultValue)`	Get the inspector's value (or the supplied default), never throws
`double`	`asDouble()`	Access the inspector's value if it's a DOUBLE (or LONG); otherwise throws exception
`double`	`asDouble(double defaultValue)`	Get the inspector's value (or the supplied default), never throws
`long`	`asLong()`	Access the inspector's value if it's a LONG (or DOUBLE); otherwise throws exception
`long`	`asLong(long defaultValue)`	Get the inspector's value (or the supplied default), never throws
`java.lang.String`	`asString()`	Access the inspector's value if it's a STRING; otherwise throws exception
`java.lang.String`	`asString(java.lang.String defaultValue)`	Get the inspector's value (or the supplied default), never throws
`byte[]`	`asUtf8()`	Access the inspector's value (in utf-8 representation) if it's a STRING; otherwise throws exception
`byte[]`	`asUtf8(byte[] defaultValue)`	Get the inspector's value (or the supplied default), never throws
`java.lang.Iterable<Inspector>`	`entries()`	Convert an array to an iterable list.
`Inspector`	`entry(int idx)`	Access an array entry.
`int`	`entryCount()`	Get the number of entries in an ARRAY (always returns 0 for non-arrays)
`Inspector`	`field(java.lang.String name)`	Access an field in an object.
`int`	`fieldCount()`	Get the number of fields in an OBJECT (always returns 0 for non-objects)
`java.lang.Iterable<java.util.Map.Entry<java.lang.String,Inspector>>`	`fields()`	Convert an object to an iterable list of (name, value) pairs.
`void`	`traverse(ArrayTraverser at)`	Traverse an array value, performing callbacks for each entry.
`void`	`traverse(ObjectTraverser ot)`	Traverse an object value, performing callbacks for each field.
`Type`	`type()`	Get the type of an inspector
`boolean`	`valid()`	Check if the inspector is valid.

Methods inherited from interface com.yahoo.data.access.Inspectable
inspect

- Method Detail
  - valid
```
boolean valid()
```
    Check if the inspector is valid. If you try to access a field or array entry that does not exist, you will get an invalid Inspector returned.
  - type
```
Type type()
```
    Get the type of an inspector
  - entryCount
```
int entryCount()
```
    Get the number of entries in an ARRAY (always returns 0 for non-arrays)
  - fieldCount
```
int fieldCount()
```
    Get the number of fields in an OBJECT (always returns 0 for non-objects)
  - asBool
```
boolean asBool()
```
    Access the inspector's value if it's a BOOLEAN; otherwise throws exception
  - asLong
```
long asLong()
```
    Access the inspector's value if it's a LONG (or DOUBLE); otherwise throws exception
  - asDouble
```
double asDouble()
```
    Access the inspector's value if it's a DOUBLE (or LONG); otherwise throws exception
  - asString
```
java.lang.String asString()
```
    Access the inspector's value if it's a STRING; otherwise throws exception
  - asUtf8
```
byte[] asUtf8()
```
    Access the inspector's value (in utf-8 representation) if it's a STRING; otherwise throws exception
  - asData
```
byte[] asData()
```
    Access the inspector's value if it's DATA; otherwise throws exception
  - asBool
```
boolean asBool(boolean defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - asLong
```
long asLong(long defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - asDouble
```
double asDouble(double defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - asString
```
java.lang.String asString(java.lang.String defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - asUtf8
```
byte[] asUtf8(byte[] defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - asData
```
byte[] asData(byte[] defaultValue)
```
    Get the inspector's value (or the supplied default), never throws
  - traverse
```
void traverse(ArrayTraverser at)
```
    Traverse an array value, performing callbacks for each entry. If the current Inspector is connected to an array value, perform callbacks to the given traverser for each entry contained in the array. Otherwise a no-op.
    
    Parameters:
    
    at - traverser callback object
  - traverse
```
void traverse(ObjectTraverser ot)
```
    Traverse an object value, performing callbacks for each field. If the current Inspector is connected to an object value, perform callbacks to the given traverser for each field contained in the object. Otherwise a no-op.
    
    Parameters:
    
    ot - traverser callback object
  - entry
```
Inspector entry(int idx)
```
    Access an array entry. If the current Inspector doesn't connect to an array value, or the given array index is out of bounds, the returned Inspector will be invalid.
    
    Parameters:
    
    idx - array index
    
    Returns:
    
    a new Inspector for the entry value
  - field
```
Inspector field(java.lang.String name)
```
    Access an field in an object. If the current Inspector doesn't connect to an object value, or the object value does not contain a field with the given symbol name, the returned Inspector will be invalid.
    
    Parameters:
    
    name - symbol name
    
    Returns:
    
    a new Inspector for the field value
  - entries
```
java.lang.Iterable<Inspector> entries()
```
    Convert an array to an iterable list. Other types will just return an empty list.
  - fields
```
java.lang.Iterable<java.util.Map.Entry<java.lang.String,Inspector>> fields()
```
    Convert an object to an iterable list of (name, value) pairs. Other types will just return an empty list.

Interface Inspector

Method Summary

Methods inherited from interface com.yahoo.data.access.Inspectable

Method Detail

valid

type

entryCount

fieldCount

asBool

asLong

asDouble

asString

asUtf8

asData

asBool

asLong

asDouble

asString

asUtf8

asData

traverse

traverse

entry

field

entries

fields