Class LazyStringArrayList

All Implemented Interfaces:
Internal.ProtobufList<String>, LazyStringList, ProtocolStringList, Iterable<String>, Collection<String>, List<String>, RandomAccess, SequencedCollection<String>

public class LazyStringArrayList extends AbstractProtobufList<String> implements LazyStringList, RandomAccess
An implementation of LazyStringList that wraps an ArrayList. Each element is one of String, ByteString, or byte[]. It caches the last one requested which is most likely the one needed next. This minimizes memory usage while satisfying the most common use cases.

Note that this implementation is not synchronized. If multiple threads access an ArrayList instance concurrently, and at least one of the threads modifies the list structurally, it must be synchronized externally. (A structural modification is any operation that adds or deletes one or more elements, or explicitly resizes the backing array; merely setting the value of an element is not a structural modification.) This is typically accomplished by synchronizing on some object that naturally encapsulates the list.

If the implementation is accessed via concurrent reads, this is thread safe. Conversions are done in a thread safe manner. It's possible that the conversion may happen more than once if two threads attempt to access the same element and the modifications were not visible to each other, but this will not result in any corruption of the list or change in behavior other than performance.

  • Field Details

  • Constructor Details

    • LazyStringArrayList

      public LazyStringArrayList()
    • LazyStringArrayList

      public LazyStringArrayList(int initialCapacity)
    • LazyStringArrayList

      public LazyStringArrayList(LazyStringList from)
    • LazyStringArrayList

      public LazyStringArrayList(List<String> from)
    • LazyStringArrayList

      private LazyStringArrayList(ArrayList<Object> list)
  • Method Details

    • emptyList

      static LazyStringArrayList emptyList()
    • mutableCopyWithCapacity

      public LazyStringArrayList mutableCopyWithCapacity(int capacity)
      Description copied from interface: Internal.ProtobufList
      Returns a mutable clone of this list with the specified capacity.
      Specified by:
      mutableCopyWithCapacity in interface Internal.ProtobufList<String>
    • get

      public String get(int index)
      Specified by:
      get in interface List<String>
      Specified by:
      get in class AbstractList<String>
    • size

      public int size()
      Specified by:
      size in interface Collection<String>
      Specified by:
      size in interface List<String>
      Specified by:
      size in class AbstractCollection<String>
    • set

      public String set(int index, String s)
      Specified by:
      set in interface List<String>
      Overrides:
      set in class AbstractProtobufList<String>
    • add

      public void add(int index, String element)
      Specified by:
      add in interface List<String>
      Overrides:
      add in class AbstractProtobufList<String>
    • add

      private void add(int index, ByteString element)
    • add

      private void add(int index, byte[] element)
    • addAll

      public boolean addAll(Collection<? extends String> c)
      Specified by:
      addAll in interface Collection<String>
      Specified by:
      addAll in interface List<String>
      Overrides:
      addAll in class AbstractProtobufList<String>
    • addAll

      public boolean addAll(int index, Collection<? extends String> c)
      Specified by:
      addAll in interface List<String>
      Overrides:
      addAll in class AbstractProtobufList<String>
    • addAllByteString

      public boolean addAllByteString(Collection<? extends ByteString> values)
      Description copied from interface: LazyStringList
      Appends all elements in the specified ByteString collection to the end of this list.
      Specified by:
      addAllByteString in interface LazyStringList
      Parameters:
      values - collection whose elements are to be added to this list
      Returns:
      true if this list changed as a result of the call
    • addAllByteArray

      public boolean addAllByteArray(Collection<byte[]> c)
      Description copied from interface: LazyStringList
      Appends all elements in the specified byte[] collection to the end of this list.
      Specified by:
      addAllByteArray in interface LazyStringList
      Parameters:
      c - collection whose elements are to be added to this list
      Returns:
      true if this list changed as a result of the call
    • remove

      public String remove(int index)
      Specified by:
      remove in interface List<String>
      Overrides:
      remove in class AbstractProtobufList<String>
    • clear

      public void clear()
      Specified by:
      clear in interface Collection<String>
      Specified by:
      clear in interface List<String>
      Overrides:
      clear in class AbstractProtobufList<String>
    • add

      public void add(ByteString element)
      Description copied from interface: LazyStringList
      Appends the specified element to the end of this list (optional operation).
      Specified by:
      add in interface LazyStringList
      Parameters:
      element - element to be appended to this list
    • add

      public void add(byte[] element)
      Description copied from interface: LazyStringList
      Appends the specified element to the end of this list (optional operation).
      Specified by:
      add in interface LazyStringList
      Parameters:
      element - element to be appended to this list
    • getRaw

      public Object getRaw(int index)
      Description copied from interface: LazyStringList
      Returns the element at the specified position in this list as an Object that will either be a String or a ByteString.
      Specified by:
      getRaw in interface LazyStringList
      Parameters:
      index - index of the element to return
      Returns:
      the element at the specified position in this list
    • getByteString

      public ByteString getByteString(int index)
      Description copied from interface: LazyStringList
      Returns the element at the specified position in this list as a ByteString.
      Specified by:
      getByteString in interface LazyStringList
      Parameters:
      index - index of the element to return
      Returns:
      the element at the specified position in this list
    • getByteArray

      public byte[] getByteArray(int index)
      Description copied from interface: LazyStringList
      Returns the element at the specified position in this list as byte[].
      Specified by:
      getByteArray in interface LazyStringList
      Parameters:
      index - index of the element to return
      Returns:
      the element at the specified position in this list
    • set

      public void set(int index, ByteString s)
      Description copied from interface: LazyStringList
      Replaces the element at the specified position in this list with the specified element (optional operation).
      Specified by:
      set in interface LazyStringList
      Parameters:
      index - index of the element to replace
      s - the element to be stored at the specified position
    • setAndReturn

      private Object setAndReturn(int index, ByteString s)
    • set

      public void set(int index, byte[] s)
      Description copied from interface: LazyStringList
      Replaces the element at the specified position in this list with the specified element (optional operation).
      Specified by:
      set in interface LazyStringList
      Parameters:
      index - index of the element to replace
      s - the element to be stored at the specified position
    • setAndReturn

      private Object setAndReturn(int index, byte[] s)
    • asString

      private static String asString(Object o)
    • asByteString

      private static ByteString asByteString(Object o)
    • asByteArray

      private static byte[] asByteArray(Object o)
    • getUnderlyingElements

      public List<?> getUnderlyingElements()
      Description copied from interface: LazyStringList
      Returns an unmodifiable List of the underlying elements, each of which is either a String or its equivalent UTF-8 encoded ByteString or byte[]. It is an error for the caller to modify the returned List, and attempting to do so will result in an UnsupportedOperationException.
      Specified by:
      getUnderlyingElements in interface LazyStringList
    • mergeFrom

      public void mergeFrom(LazyStringList other)
      Description copied from interface: LazyStringList
      Merges all elements from another LazyStringList into this one. This method differs from List.addAll(Collection) on that underlying byte arrays are copied instead of reference shared. Immutable API doesn't need to use this method as byte[] is not used there at all.
      Specified by:
      mergeFrom in interface LazyStringList
    • asByteArrayList

      public List<byte[]> asByteArrayList()
      Description copied from interface: LazyStringList
      Returns a mutable view of this list. Changes to the view will be made into the original list. This method is used in mutable API only.
      Specified by:
      asByteArrayList in interface LazyStringList
    • asByteStringList

      public List<ByteString> asByteStringList()
      Description copied from interface: ProtocolStringList
      Returns a view of the data as a list of ByteStrings.
      Specified by:
      asByteStringList in interface ProtocolStringList
    • getUnmodifiableView

      public LazyStringList getUnmodifiableView()
      Description copied from interface: LazyStringList
      Returns an unmodifiable view of the list.
      Specified by:
      getUnmodifiableView in interface LazyStringList