Package org.mozilla.javascript

Class NativeJavaList

java.lang.Object
org.mozilla.javascript.NativeJavaObject
org.mozilla.javascript.NativeJavaList
All Implemented Interfaces:
Serializable, Scriptable, SymbolScriptable, Wrapper
public class NativeJavaList extends NativeJavaObject
NativeJavaList is a wrapper for java objects implementing java.util.List interface. This wrapper delegates index based access in javascript (like value[x] = 3) to the according List.get(int), List.set(int, Object) and List.add(Object) methods. This allows you to use java lists in many places like a javascript Array.

Supported functions:

  • index based access is delegated to List.get/set/add. If index >= length, the skipped elements will be filled with null values
  • iterator support with for...of (provided by NativeJavaObject for all iterables)
  • when iterating with for .. in (or for each .. in) then getIds + index based access is used.
  • reading and setting length property. When modifying the length property, the list is either truncated or will be filled with null values up to length
  • deleting entries: delete value[index] will be equivalent with value[index] = null and is implemented to provide array compatibility.
Important: JavaList does not support sparse arrays. So setting the length property to a high value or writing to a high index may allocate a lot of memory.

Note: Although JavaList looks like a javascript-Array, it is not an Array. Some methods behave very similar like Array.indexOf and java.util.List.indexOf, others are named differently like Array.includes vs. java.util.List.contains. Especially forEach is different in Array and java.util.List. Also deleting entries will set entries to null instead to Undefined

See Also:

  • Constructor Details

  • Method Details

    • getClassName

      public String getClassName()
      Description copied from interface: Scriptable
      Get the name of the set of objects implemented by this Java class. This corresponds to the [[Class]] operation in ECMA and is used by Object.prototype.toString() in ECMA.

      See ECMA 8.6.2 and 15.2.4.2.

      Specified by:
      getClassName in interface Scriptable
      Overrides:
      getClassName in class NativeJavaObject

    • has

      public boolean has(String name, Scriptable start)
      Description copied from interface: Scriptable
      Indicates whether or not a named property is defined in an object.

      Does not traverse the prototype chain.

      The property is specified by a String name as defined for the get method.

      Specified by:
      has in interface Scriptable
      Overrides:
      has in class NativeJavaObject
      Parameters:
      name - the name of the property
      start - the object in which the lookup began
      Returns:
      true if and only if the named property is found in the object
      See Also:

    • has

      public boolean has(int index, Scriptable start)
      Description copied from interface: Scriptable
      Indicates whether or not an indexed property is defined in an object.

      Does not traverse the prototype chain.

      The property is specified by an integral index as defined for the get method.

      Specified by:
      has in interface Scriptable
      Overrides:
      has in class NativeJavaObject
      Parameters:
      index - the numeric index for the property
      start - the object in which the lookup began
      Returns:
      true if and only if the indexed property is found in the object
      See Also:

    • delete

      public void delete(int index)
      Description copied from interface: Scriptable
      Removes a property from this object.

      The property is specified by an integral index as defined for get.

      To delete properties defined in a prototype chain, see deleteProperty in ScriptableObject.

      Identical to delete(String) except that an integral index is used to select the property.

      Specified by:
      delete in interface Scriptable
      Overrides:
      delete in class NativeJavaObject
      Parameters:
      index - the numeric index for the property
      See Also:

    • has

      public boolean has(Symbol key, Scriptable start)
      Description copied from interface: SymbolScriptable
      Return true if the specified property exists.
      Specified by:
      has in interface SymbolScriptable
      Overrides:
      has in class NativeJavaObject

    • get

      public Object get(String name, Scriptable start)
      Description copied from interface: Scriptable
      Get a named property from the object.

      Looks property up in this object and returns the associated value if found. Returns NOT_FOUND if not found. Note that this method is not expected to traverse the prototype chain. This is different from the ECMA [[Get]] operation.

      Depending on the property selector, the runtime will call this method or the form of get that takes an integer:

      Code examples
      JavaScript codeJava code
      a.b a.get("b", a)
      a["foo"] a.get("foo", a)
      a[3] a.get(3, a)
      a["3"] a.get(3, a)
      a[3.0] a.get(3, a)
      a["3.0"] a.get("3.0", a)
      a[1.1] a.get("1.1", a)
      a[-4] a.get(-4, a)

      The values that may be returned are limited to the following:

      • java.lang.Boolean objects
      • java.lang.String objects
      • java.lang.Number objects
      • org.mozilla.javascript.Scriptable objects
      • null
      • The value returned by Context.getUndefinedValue()
      • NOT_FOUND
      Specified by:
      get in interface Scriptable
      Overrides:
      get in class NativeJavaObject
      Parameters:
      name - the name of the property
      start - the object in which the lookup began
      Returns:
      the value of the property (may be null), or NOT_FOUND
      See Also:

    • get

      public Object get(int index, Scriptable start)
      Description copied from interface: Scriptable
      Get a property from the object selected by an integral index.

      Identical to get(String, Scriptable) except that an integral index is used to select the property.

      Specified by:
      get in interface Scriptable
      Overrides:
      get in class NativeJavaObject
      Parameters:
      index - the numeric index for the property
      start - the object in which the lookup began
      Returns:
      the value of the property (may be null), or NOT_FOUND
      See Also:

    • get

      public Object get(Symbol key, Scriptable start)
      Description copied from interface: SymbolScriptable
      Return the value of the property with the specified key, or NOT_FOUND.
      Specified by:
      get in interface SymbolScriptable
      Overrides:
      get in class NativeJavaObject

    • put

      public void put(int index, Scriptable start, Object value)
      Description copied from interface: Scriptable
      Sets an indexed property in this object.

      The property is specified by an integral index as defined for get.

      Identical to put(String, Scriptable, Object) except that an integral index is used to select the property.

      Specified by:
      put in interface Scriptable
      Overrides:
      put in class NativeJavaObject
      Parameters:
      index - the numeric index for the property
      start - the object whose property is being set
      value - value to set the property to
      See Also:

    • put

      public void put(String name, Scriptable start, Object value)
      Description copied from interface: Scriptable
      Sets a named property in this object.

      The property is specified by a string name as defined for get.

      The possible values that may be passed in are as defined for get. A class that implements this method may choose to ignore calls to set certain properties, in which case those properties are effectively read-only.

      For properties defined in a prototype chain, use putProperty in ScriptableObject.

      Note that if a property a is defined in the prototype p of an object o, then evaluating o.a = 23 will cause set to be called on the prototype p with o as the start parameter. To preserve JavaScript semantics, it is the Scriptable object's responsibility to modify o.

      This design allows properties to be defined in prototypes and implemented in terms of getters and setters of Java values without consuming slots in each instance.

      The values that may be set are limited to the following:

      • java.lang.Boolean objects
      • java.lang.String objects
      • java.lang.Number objects
      • org.mozilla.javascript.Scriptable objects
      • null
      • The value returned by Context.getUndefinedValue()

      Arbitrary Java objects may be wrapped in a Scriptable by first calling Context.toObject. This allows the property of a JavaScript object to contain an arbitrary Java object as a value.

      Note that has will be called by the runtime first before set is called to determine in which object the property is defined. Note that this method is not expected to traverse the prototype chain, which is different from the ECMA [[Put]] operation.

      Specified by:
      put in interface Scriptable
      Overrides:
      put in class NativeJavaObject
      Parameters:
      name - the name of the property
      start - the object whose property is being set
      value - value to set the property to
      See Also:

    • getIds

      public Object[] getIds()
      Description copied from interface: Scriptable
      Get an array of property ids.

      Not all property ids need be returned. Those properties whose ids are not returned are considered non-enumerable.

      Specified by:
      getIds in interface Scriptable
      Overrides:
      getIds in class NativeJavaObject
      Returns:
      an array of Objects. Each entry in the array is either a java.lang.String or a java.lang.Number

    • equals

      public boolean equals(Object obj)
      Overrides:
      equals in class NativeJavaObject

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class NativeJavaObject