ObjectList (Juneau)

java.lang.Object
+
- java.util.AbstractCollection<E>
- +
  - java.util.AbstractList<E>
  - +
    - java.util.AbstractSequentialList<E>
    - +
      - java.util.LinkedList<Object>
      - +
        +
        org.apache.juneau.ObjectList
        +
        +
      +
    +
  +
+

+
+
All Implemented Interfaces:
+
Serializable, Cloneable, Iterable<Object>, Collection<Object>, Deque<Object>, List<Object>, Queue<Object>
+
+
+
+
```
public class ObjectList
+extends LinkedList<Object>
```
+
Java implementation of a JSON array. +
+ An extension of LinkedList, so all methods available to in that class are also available + to this class. +
+ Note that the use of this class is optional. The serializers will accept any objects that implement + the Collection interface. But this class provides some useful additional functionality + when working with JSON models constructed from Java Collections Framework objects. For example, a + constructor is provided for converting a JSON array string directly into a List. It also contains + accessor methods for to avoid common typecasting when accessing elements in a list. + +
Examples
+
+ // Construct an empty List + List l = new ObjectList(); + + // Construct a list of objects using various methods + l = new ObjectList().append("foo").append(123).append(true); + l = new ObjectList().append("foo", 123, true); // Equivalent + l = new ObjectList("foo", 123, true); // Equivalent + + // Construct a list of integers from JSON + l = new ObjectList("[1,2,3]"); + + // Construct a list of generic ObjectMap objects from JSON + l = new ObjectList("[{foo:'bar'},{baz:'bing'}]"); + + // Construct a list of integers from XML + String xml = "<array><number>1</number><number>2</number><number>3</number></array>"; + l = new ObjectList(xml, DataFormat.XML); + l = (List)XmlParser.DEFAULT.parse(xml); // Equivalent + l = (List)XmlParser.DEFAULT.parse(Object.class, xml); // Equivalent + l = XmlParser.DEFAULT.parse(List.class, xml); // Equivalent + l = XmlParser.DEFAULT.parse(ObjectList.class, xml); // Equivalent + + // Construct JSON from ObjectList + l = new ObjectList("[{foo:'bar'},{baz:'bing'}]"); + String json = l.toString(); // Produces "[{foo:'bar'},{baz:'bing'}]" + json = l.toString(JsonSerializer.DEFAULT_CONDENSED); // Equivalent + json = JsonSerializer.DEFAULT_CONDENSED.serialize(l); // Equivalent + + // Get one of the entries in the list as an Integer + l = new ObjectList("[1,2,3]"); + Integer i = l.getInt(1); + i = l.get(Integer.class, 1); // Equivalent + + // Get one of the entries in the list as an Float + l = new ObjectList("[1,2,3]"); + Float f = l.getFloat(1); // Returns 2f + f = l.get(Float.class, 1); // Equivalent + + // Same as above, except converted to a String + l = new ObjectList("[1,2,3]"); + String s = l.getString(1); // Returns "2" + s = l.get(String.class, 1); // Equivalent + + // Get one of the entries in the list as a bean (converted to a bean if it isn't already one) + l = new ObjectList("[{name:'John Smith',age:45}]"); + Person p = l.get(Person.class, 0); + + // Iterate over a list of beans using the elements() method + ObjectList ObjectList = new ObjectList("[{name:'John Smith',age:45}]"); + for (Person p : ObjectList.elements(Person.class) { + // Do something with p + } +
+
+ This class is not thread safe. +
+
+
Author:
+
James Bognar (james.bognar@salesforce.com)
+
See Also:
+
Serialized Form
+
+

+ +

+ + +
Field Summary
+ + + + + + + + + + +
Fields
Modifier and Type Field and Description
static ObjectList EMPTY_LIST +
An empty read-only ObjectList.
+
+
- + + +
  Fields inherited from class java.util.AbstractList
  +modCount
+

Fields
Modifier and Type	Field and Description
`static ObjectList`	`EMPTY_LIST` + An empty read-only ObjectList. +

+ +

Constructor Summary

+ + + + + + + + + + + + + + + + + + + + + + + + + + +

Constructors
Constructor and Description
`ObjectList()` + Construct an empty JSON array. +
`ObjectList(BeanContext beanContext)` + Construct an empty JSON array with the specified bean context. +
`ObjectList(CharSequence s)` + Shortcut for `new ObjectList(String,JsonParser.DEFAULT);` +
`ObjectList(CharSequence s, + Parser p)` + Construct a JSON array directly from text using the specified parser. +
`ObjectList(Collection<?> c)` + Construct a JSON array and fill it with the specified collection of objects. +
`ObjectList(Object... o)` + Construct a JSON array and fill it with the specified objects. +
`ObjectList(Reader r, + Parser p)` + Construct a JSON array directly from a reader using the specified parser. +

+ +

+ + +

Method Summary

+ + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`ObjectList`	`append(Object... o)` + Convenience method for adding multiple objects to this list. +
`Object`	`deleteAt(String path)` + Similar to `remove(int)`,but the key is a slash-delimited + path used to traverse entries in this POJO. +
`<E> Iterable<E>`	`elements(Class<E> childType)` + Creates an `Iterable` with elements of the specified child type. +
`<T> T`	`get(Class<T> type, + int index)` + Get the entry at the specified index, converted to the specified type (if possible). +
`<T> T`	`getAt(Class<T> type, + String path)` + Same as `get(Class,int)`, but the key is a slash-delimited + path used to traverse entries in this POJO. +
`Boolean`	`getBoolean(int index)` + Shortcut for calling `get(Boolean.class, index)`. +
`ClassMeta<?>`	`getClassMeta(int index)` + Returns the `ClassMeta` of the class of the object at the specified index. +
`Integer`	`getInt(int index)` + Shortcut for calling `get(Integer.class, index)`. +
`List<?>`	`getList(int index)` + Shortcut for calling `get(List.class, index)`. +
`Long`	`getLong(int index)` + Shortcut for calling `get(Long.class, index)`. +
`Map<?,?>`	`getMap(int index)` + Shortcut for calling `get(Map.class, index)`. +
`ObjectList`	`getObjectList(int index)` + Shortcut for calling `get(ObjectList.class, index)`. +
`ObjectMap`	`getObjectMap(int index)` + Shortcut for calling `get(ObjectMap.class, index)`. +
`String`	`getString(int index)` + Shortcut for calling `get(String.class, index)`. +
`Object`	`postAt(String path, + Object o)` + Similar to `putAt(String,Object)`, but used to append + to collections and arrays. +
`Object`	`putAt(String path, + Object o)` + Same as `set(int,Object)`, but the key is a slash-delimited + path used to traverse entries in this POJO. +
`void`	`serializeTo(Writer w)` + Convenience method for serializing this ObjectList to the specified Writer using + the JsonSerializer.DEFAULT serializer. +
`ObjectList`	`setBeanContext(BeanContext beanContext)` + Override the default bean context used for converting POJOs. +
`String`	`toString()` + Serialize this array to JSON using the `JsonSerializer.DEFAULT` serializer. +
`String`	`toString(WriterSerializer serializer)` + Serialize this array to a string using the specified serializer. +

+ + +
Methods inherited from class java.util.LinkedList
+add, add, addAll, addAll, addFirst, addLast, clear, clone, contains, descendingIterator, element, get, getFirst, getLast, indexOf, lastIndexOf, listIterator, offer, offerFirst, offerLast, peek, peekFirst, peekLast, poll, pollFirst, pollLast, pop, push, remove, remove, remove, removeFirst, removeFirstOccurrence, removeLast, removeLastOccurrence, set, size, spliterator, toArray, toArray

+ + +
Methods inherited from class java.util.AbstractSequentialList
+iterator

+ + +
Methods inherited from class java.util.AbstractList
+equals, hashCode, listIterator, removeRange, subList

+ + +
Methods inherited from class java.util.AbstractCollection
+containsAll, isEmpty, removeAll, retainAll

+ + +
Methods inherited from class java.lang.Object
+finalize, getClass, notify, notifyAll, wait, wait, wait

+ + +
Methods inherited from interface java.util.List
+containsAll, equals, hashCode, isEmpty, iterator, listIterator, removeAll, replaceAll, retainAll, sort, subList

+ + +
Methods inherited from interface java.util.Deque
+iterator

+ + +
Methods inherited from interface java.util.Collection
+parallelStream, removeIf, stream

+ + +
Methods inherited from interface java.lang.Iterable
+forEach

+ +
- + + +
  Field Detail
  + + + +
  - +
    EMPTY_LIST
    +
```
public static final ObjectList EMPTY_LIST
```
    +
    An empty read-only ObjectList.
    +
  +
+ +
- + + +
  Constructor Detail
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(CharSequence s,
+                  Parser p)
+           throws ParseException
```
    +
    Construct a JSON array directly from text using the specified parser.
    +
    +
    Parameters:
    +
    s - The string being parsed.
    +
    p - The parser to use to parse the input.
    +
    Throws:
    +
    ParseException - If the input contains a syntax error or is malformed.
    +
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(CharSequence s)
+           throws ParseException
```
    +
    Shortcut for new ObjectList(String,JsonParser.DEFAULT);
    +
    +
    Parameters:
    +
    s - The string being parsed.
    +
    Throws:
    +
    ParseException - If the input contains a syntax error or is malformed.
    +
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(Reader r,
+                  Parser p)
+           throws ParseException,
+                  IOException
```
    +
    Construct a JSON array directly from a reader using the specified parser.
    +
    +
    Parameters:
    +
    r - The reader to read from. Will automatically be wrapped in a BufferedReader if it isn't already a BufferedReader.
    +
    p - The parser to use to parse the input.
    +
    Throws:
    +
    ParseException - If the input contains a syntax error or is malformed.
    +
    IOException - If a problem occurred trying to read from the reader.
    +
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList()
```
    +
    Construct an empty JSON array. (i.e. an empty LinkedList).
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(BeanContext beanContext)
```
    +
    Construct an empty JSON array with the specified bean context. (i.e. an empty LinkedList).
    +
    +
    Parameters:
    +
    beanContext - The bean context to associate with this object list for creating beans.
    +
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(Object... o)
```
    +
    Construct a JSON array and fill it with the specified objects.
    +
    +
    Parameters:
    +
    o - A list of objects to add to this list.
    +
    +
  + + + +
  - +
    ObjectList
    +
```
public ObjectList(Collection<?> c)
```
    +
    Construct a JSON array and fill it with the specified collection of objects.
    +
    +
    Parameters:
    +
    c - A list of objects to add to this list.
    +
    +
  +
+ +
- + + +
  Method Detail
  + + + +
  - +
    setBeanContext
    +
```
public ObjectList setBeanContext(BeanContext beanContext)
```
    +
    Override the default bean context used for converting POJOs. +
    + Default is BeanContext.DEFAULT, which is sufficient in most cases. +
    + Useful if you're serializing/parsing beans with transforms defined.
    +
    +
    Parameters:
    +
    beanContext - The new bean context.
    +
    Returns:
    +
    This object (for method chaining).
    +
    +
  + + + +
  - +
    append
    +
```
public ObjectList append(Object... o)
```
    +
    Convenience method for adding multiple objects to this list.
    +
    +
    Parameters:
    +
    o - The objects to add to the list.
    +
    Returns:
    +
    This object (for method chaining).
    +
    +
  + + + +
  - +
    get
    +
```
public <T> T get(Class<T> type,
+                 int index)
```
    +
    Get the entry at the specified index, converted to the specified type (if possible). +
    + See BeanContext.convertToType(Object, ClassMeta) for the list of valid data conversions.
    +
    +
    Type Parameters:
    +
    T - The type of object to convert the entry to.
    +
    Parameters:
    +
    type - The type of object to convert the entry to.
    +
    index - The index into this list.
    +
    Returns:
    +
    The converted entry.
    +
    +
  + + + +
  - +
    getString
    +
```
public String getString(int index)
```
    +
    Shortcut for calling get(String.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    +
  + + + +
  - +
    getInt
    +
```
public Integer getInt(int index)
```
    +
    Shortcut for calling get(Integer.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getBoolean
    +
```
public Boolean getBoolean(int index)
```
    +
    Shortcut for calling get(Boolean.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getLong
    +
```
public Long getLong(int index)
```
    +
    Shortcut for calling get(Long.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getMap
    +
```
public Map<?,?> getMap(int index)
```
    +
    Shortcut for calling get(Map.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getList
    +
```
public List<?> getList(int index)
```
    +
    Shortcut for calling get(List.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getObjectMap
    +
```
public ObjectMap getObjectMap(int index)
```
    +
    Shortcut for calling get(ObjectMap.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getObjectList
    +
```
public ObjectList getObjectList(int index)
```
    +
    Shortcut for calling get(ObjectList.class, index).
    +
    +
    Parameters:
    +
    index - The index.
    +
    Returns:
    +
    The converted value.
    +
    Throws:
    +
    InvalidDataConversionException - If value cannot be converted.
    +
    +
  + + + +
  - +
    getAt
    +
```
public <T> T getAt(Class<T> type,
+                   String path)
```
    +
    Same as get(Class,int), but the key is a slash-delimited + path used to traverse entries in this POJO. +
    + For example, the following code is equivalent: +
    +
    + ObjectMap m = getObjectMap(); + + // Long way + long l = m.getObjectMap("foo").getObjectList("bar").getObjectMap("0").getLong("baz"); + + // Using this method + long l = m.getAt(long.class, "foo/bar/0/baz"); +
    +
    + This method uses the PojoRest class to perform the lookup, so the map can contain + any of the various class types that the PojoRest class supports (e.g. beans, collections, arrays). +
    +
    +
    Type Parameters:
    +
    T - The class type.
    +
    Parameters:
    +
    type - The class type.
    +
    path - The path to the entry.
    +
    Returns:
    +
    The value, or null if the entry doesn't exist.
    +
    +
  + + + +
  - +
    putAt
    +
```
public Object putAt(String path,
+                    Object o)
```
    +
    Same as set(int,Object), but the key is a slash-delimited + path used to traverse entries in this POJO. +
    + For example, the following code is equivalent: +
    +
    + ObjectMap m = getObjectMap(); + + // Long way + m.getObjectMap("foo").getObjectList("bar").getObjectMap("0").put("baz", 123); + + // Using this method + m.putAt("foo/bar/0/baz", 123); +
    +
    + This method uses the PojoRest class to perform the lookup, so the map can contain + any of the various class types that the PojoRest class supports (e.g. beans, collections, arrays). +
    +
    +
    Parameters:
    +
    path - The path to the entry.
    +
    o - The new value.
    +
    Returns:
    +
    The previous value, or null if the entry doesn't exist.
    +
    +
  + + + +
  - +
    postAt
    +
```
public Object postAt(String path,
+                     Object o)
```
    +
    Similar to putAt(String,Object), but used to append + to collections and arrays. +
    + For example, the following code is equivalent: +
    +
    + ObjectMap m = getObjectMap(); + + // Long way + m.getObjectMap("foo").getObjectList("bar").append(123); + + // Using this method + m.postAt("foo/bar", 123); +
    +
    + This method uses the PojoRest class to perform the lookup, so the map can contain + any of the various class types that the PojoRest class supports (e.g. beans, collections, arrays). +
    +
    +
    Parameters:
    +
    path - The path to the entry.
    +
    o - The new value.
    +
    Returns:
    +
    The previous value, or null if the entry doesn't exist.
    +
    +
  + + + +
  - +
    deleteAt
    +
```
public Object deleteAt(String path)
```
    +
    Similar to remove(int),but the key is a slash-delimited + path used to traverse entries in this POJO. +
    + For example, the following code is equivalent: +
    +
    + ObjectMap m = getObjectMap(); + + // Long way + m.getObjectMap("foo").getObjectList("bar").getObjectMap(1).remove("baz"); + + // Using this method + m.deleteAt("foo/bar/0/baz"); +
    +
    + This method uses the PojoRest class to perform the lookup, so the map can contain + any of the various class types that the PojoRest class supports (e.g. beans, collections, arrays). +
    +
    +
    Parameters:
    +
    path - The path to the entry.
    +
    Returns:
    +
    The previous value, or null if the entry doesn't exist.
    +
    +
  + + + +
  - +
    elements
    +
```
public <E> Iterable<E> elements(Class<E> childType)
```
    +
    Creates an Iterable with elements of the specified child type. +
    + Attempts to convert the child objects to the correct type if they aren't already the correct type. +
    + The next() method on the returned iterator may throw a InvalidDataConversionException if + the next element cannot be converted to the specified type. +
    + See BeanContext.convertToType(Object, ClassMeta) for a description of valid conversions. + +
    +
    Example:
    +
    +
    + // Iterate over a list of ObjectMaps. + ObjectList l = new ObjectList("[{foo:'bar'},{baz:123}]"); + for (ObjectMap m : l.elements(ObjectMap.class)) { + // Do something with m. + } + + // Iterate over a list of ints. + ObjectList l = new ObjectList("[1,2,3]"); + for (Integer i : l.elements(Integer.class)) { + // Do something with i. + } + + // Iterate over a list of beans. + // Automatically converts to beans. + ObjectList l = new ObjectList("[{name:'John Smith',age:45}]"); + for (Person p : l.elements(Person.class)) { + // Do something with p. + } +
    +
    +
    +
    +
    Type Parameters:
    +
    E - The child object type.
    +
    Parameters:
    +
    childType - The child object type.
    +
    Returns:
    +
    A new Iterable object over this list.
    +
    +
  + + + +
  - +
    getClassMeta
    +
```
public ClassMeta<?> getClassMeta(int index)
```
    +
    Returns the ClassMeta of the class of the object at the specified index.
    +
    +
    Parameters:
    +
    index - An index into this list, zero-based.
    +
    Returns:
    +
    The data type of the object at the specified index, or null if the value is null.
    +
    +
  + + + +
  - +
    toString
    +
```
public String toString(WriterSerializer serializer)
+                throws SerializeException
```
    +
    Serialize this array to a string using the specified serializer.
    +
    +
    Parameters:
    +
    serializer - The serializer to use to convert this object to a string.
    +
    Returns:
    +
    This object as a serialized string.
    +
    Throws:
    +
    SerializeException - If a problem occurred trying to convert the output.
    +
    +
  + + + +
  - +
    toString
    +
```
public String toString()
```
    +
    Serialize this array to JSON using the JsonSerializer.DEFAULT serializer.
    +
    +
    Overrides:
    +
    toString in class AbstractCollection<Object>
    +
    +
  + + + +
  - +
    serializeTo
    +
```
public void serializeTo(Writer w)
+                 throws IOException,
+                        SerializeException
```
    +
    Convenience method for serializing this ObjectList to the specified Writer using + the JsonSerializer.DEFAULT serializer.
    +
    +
    Parameters:
    +
    w - The writer to send the serialized contents of this object.
    +
    Throws:
    +
    IOException - If a problem occurred trying to write to the writer.
    +
    SerializeException - If a problem occurred trying to convert the output.
    +
    +
  +
+

Class ObjectList

Examples

Field Summary

Fields inherited from class java.util.AbstractList

Constructor Summary

Method Summary

Methods inherited from class java.util.LinkedList

Methods inherited from class java.util.AbstractSequentialList

Methods inherited from class java.util.AbstractList

Methods inherited from class java.util.AbstractCollection

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.List

Methods inherited from interface java.util.Deque

Methods inherited from interface java.util.Collection

Methods inherited from interface java.lang.Iterable

Field Detail

EMPTY_LIST

Constructor Detail

ObjectList

ObjectList

ObjectList

ObjectList

ObjectList

ObjectList

ObjectList

Method Detail

setBeanContext

append

get

getString

getInt

getBoolean

getLong

getMap

getList

getObjectMap

getObjectList

getAt

putAt

postAt

deleteAt

elements

getClassMeta

toString

toString

serializeTo