ImmutableDoubleArray (Guava: Google Core Libraries for Java 23.0 API)

java.lang.Object
- com.google.common.primitives.ImmutableDoubleArray

All Implemented Interfaces:

Serializable
```
@Beta
 @GwtCompatible
public final class ImmutableDoubleArray
extends Object
implements Serializable
```
An immutable array of double values, with an API resembling List.
Advantages compared to double[]:
- All the many well-known advantages of immutability (read Effective Java, second edition, Item 15).
- Has the value-based (not identity-based) equals(java.lang.Object), hashCode(), and toString() behavior you expect.
- Offers useful operations beyond just get and length, so you don't have to hunt through classes like Arrays and Doubles for them.
- Supports a copy-free subArray(int, int) view, so methods that accept this type don't need to add overloads that accept start and end indexes.
- Can be streamed without "breaking the chain": foo.getBarDoubles().stream()....
- Access to all collection-based utilities via asList() (though at the cost of allocating garbage).
Disadvantages compared to double[]:
- Memory footprint has a fixed overhead (about 24 bytes per instance).
- Some construction use cases force the data to be copied (though several construction APIs are offered that don't).
- Can't be passed directly to methods that expect double[] (though the most common utilities do have replacements here).
- Dependency on com.google.common / Guava.
Advantages compared to ImmutableList<Double>:
- Improved memory compactness and locality.
- Can be queried without allocating garbage.
- Access to DoubleStream features (like DoubleStream.sum()) using stream() instead of the awkward stream().mapToDouble(v -> v).
Disadvantages compared to ImmutableList<Double>:
- Can't be passed directly to methods that expect Iterable, Collection, or List (though the most common utilities do have replacements here, and there is a lazy asList() view).
Since:

22.0

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class ImmutableDoubleArray.Builder
A builder for ImmutableDoubleArray instances; obtained using builder(int).

Nested Classes
Modifier and Type	Class and Description
`static class`	`ImmutableDoubleArray.Builder` A builder for `ImmutableDoubleArray` instances; obtained using `builder(int)`.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`List<Double>`	`asList()` Returns an immutable view of this array's values as a `List`; note that `double` values are boxed into `Double` instances on demand, which can be very expensive.
`static ImmutableDoubleArray.Builder`	`builder()` Returns a new, empty builder for `ImmutableDoubleArray` instances, with a default initial capacity.
`static ImmutableDoubleArray.Builder`	`builder(int initialCapacity)` Returns a new, empty builder for `ImmutableDoubleArray` instances, sized to hold up to `initialCapacity` values without resizing.
`boolean`	`contains(double target)` Returns `true` if `target` is present at any index in this array.
`static ImmutableDoubleArray`	`copyOf(Collection<Double> values)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`copyOf(double[] values)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`copyOf(DoubleStream stream)` Returns an immutable array containing all the values from `stream`, in order.
`static ImmutableDoubleArray`	`copyOf(Iterable<Double> values)` Returns an immutable array containing the given values, in order.
`boolean`	`equals(Object object)`
`void`	`forEach(DoubleConsumer consumer)` Invokes `consumer` for each value contained in this array, in order.
`double`	`get(int index)` Returns the `double` value present at the given index.
`int`	`hashCode()` Returns an unspecified hash code for the contents of this immutable array.
`int`	`indexOf(double target)` Returns the smallest index for which `get(int)` returns `target`, or `-1` if no such index exists.
`boolean`	`isEmpty()` Returns `true` if there are no values in this array (`length()` is zero).
`int`	`lastIndexOf(double target)` Returns the largest index for which `get(int)` returns `target`, or `-1` if no such index exists.
`int`	`length()` Returns the number of values in this array.
`static ImmutableDoubleArray`	`of()` Returns the empty array.
`static ImmutableDoubleArray`	`of(double e0)` Returns an immutable array containing a single value.
`static ImmutableDoubleArray`	`of(double first, double... rest)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`of(double e0, double e1)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`of(double e0, double e1, double e2)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`of(double e0, double e1, double e2, double e3)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`of(double e0, double e1, double e2, double e3, double e4)` Returns an immutable array containing the given values, in order.
`static ImmutableDoubleArray`	`of(double e0, double e1, double e2, double e3, double e4, double e5)` Returns an immutable array containing the given values, in order.
`DoubleStream`	`stream()` Returns a stream over the values in this array, in order.
`ImmutableDoubleArray`	`subArray(int startIndex, int endIndex)` Returns a new immutable array containing the values in the specified range.
`double[]`	`toArray()` Returns a new, mutable copy of this array's values, as a primitive `double[]`.
`String`	`toString()` Returns a string representation of this array in the same form as `Arrays.toString(double[])`, for example `"[1, 2, 3]"`.
`ImmutableDoubleArray`	`trimmed()` Returns an immutable array containing the same values as `this` array.

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

- Method Detail
  - of
```
public static ImmutableDoubleArray of()
```
    Returns the empty array.
  - of
```
public static ImmutableDoubleArray of(double e0)
```
    Returns an immutable array containing a single value.
  - of
```
public static ImmutableDoubleArray of(double e0,
                                      double e1)
```
    Returns an immutable array containing the given values, in order.
  - of
```
public static ImmutableDoubleArray of(double e0,
                                      double e1,
                                      double e2)
```
    Returns an immutable array containing the given values, in order.
  - of
```
public static ImmutableDoubleArray of(double e0,
                                      double e1,
                                      double e2,
                                      double e3)
```
    Returns an immutable array containing the given values, in order.
  - of
```
public static ImmutableDoubleArray of(double e0,
                                      double e1,
                                      double e2,
                                      double e3,
                                      double e4)
```
    Returns an immutable array containing the given values, in order.
  - of
```
public static ImmutableDoubleArray of(double e0,
                                      double e1,
                                      double e2,
                                      double e3,
                                      double e4,
                                      double e5)
```
    Returns an immutable array containing the given values, in order.
  - of
```
public static ImmutableDoubleArray of(double first,
                                      double... rest)
```
    Returns an immutable array containing the given values, in order.
  - copyOf
```
public static ImmutableDoubleArray copyOf(double[] values)
```
    Returns an immutable array containing the given values, in order.
  - copyOf
```
public static ImmutableDoubleArray copyOf(Collection<Double> values)
```
    Returns an immutable array containing the given values, in order.
  - copyOf
```
public static ImmutableDoubleArray copyOf(Iterable<Double> values)
```
    Returns an immutable array containing the given values, in order.
    Performance note: this method delegates to copyOf(Collection) if values is a Collection. Otherwise it creates a builder(int) and uses ImmutableDoubleArray.Builder.addAll(Iterable), with all the performance implications associated with that.
  - copyOf
```
public static ImmutableDoubleArray copyOf(DoubleStream stream)
```
    Returns an immutable array containing all the values from stream, in order.
  - builder
```
public static ImmutableDoubleArray.Builder builder(int initialCapacity)
```
    Returns a new, empty builder for ImmutableDoubleArray instances, sized to hold up to initialCapacity values without resizing. The returned builder is not thread-safe.
    Performance note: When feasible, initialCapacity should be the exact number of values that will be added, if that knowledge is readily available. It is better to guess a value slightly too high than slightly too low. If the value is not exact, the ImmutableDoubleArray that is built will very likely occupy more memory than strictly necessary; to trim memory usage, build using builder.build().trimmed().
  - builder
```
public static ImmutableDoubleArray.Builder builder()
```
    Returns a new, empty builder for ImmutableDoubleArray instances, with a default initial capacity. The returned builder is not thread-safe.
    Performance note: The ImmutableDoubleArray that is built will very likely occupy more memory than necessary; to trim memory usage, build using builder.build().trimmed().
  - length
```
public int length()
```
    Returns the number of values in this array.
  - isEmpty
```
public boolean isEmpty()
```
    Returns true if there are no values in this array (length() is zero).
  - get
```
public double get(int index)
```
    Returns the double value present at the given index.
    
    Throws:
    
    IndexOutOfBoundsException - if index is negative, or greater than or equal to length()
  - indexOf
```
public int indexOf(double target)
```
    Returns the smallest index for which get(int) returns target, or -1 if no such index exists. Values are compared as if by Double.equals(java.lang.Object). Equivalent to asList().indexOf(target).
  - lastIndexOf
```
public int lastIndexOf(double target)
```
    Returns the largest index for which get(int) returns target, or -1 if no such index exists. Values are compared as if by Double.equals(java.lang.Object). Equivalent to asList().lastIndexOf(target).
  - contains
```
public boolean contains(double target)
```
    Returns true if target is present at any index in this array. Values are compared as if by Double.equals(java.lang.Object). Equivalent to asList().contains(target).
  - forEach
```
public void forEach(DoubleConsumer consumer)
```
    Invokes consumer for each value contained in this array, in order.
  - stream
```
public DoubleStream stream()
```
    Returns a stream over the values in this array, in order.
  - toArray
```
public double[] toArray()
```
    Returns a new, mutable copy of this array's values, as a primitive double[].
  - subArray
```
public ImmutableDoubleArray subArray(int startIndex,
                                     int endIndex)
```
    Returns a new immutable array containing the values in the specified range.
    Performance note: The returned array has the same full memory footprint as this one does (no actual copying is performed). To reduce memory usage, use subArray(start, end).trimmed().
  - asList
```
public List<Double> asList()
```
    Returns an immutable view of this array's values as a List; note that double values are boxed into Double instances on demand, which can be very expensive. The returned list should be used once and discarded. For any usages beyond that, pass the returned list to ImmutableList.copyOf and use that list instead.
  - equals
```
public boolean equals(@Nullable
                      Object object)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Returns an unspecified hash code for the contents of this immutable array.
    
    Overrides:
    
    hashCode in class Object
  - toString
```
public String toString()
```
    Returns a string representation of this array in the same form as Arrays.toString(double[]), for example "[1, 2, 3]".
    
    Overrides:
    
    toString in class Object
  - trimmed
```
public ImmutableDoubleArray trimmed()
```
    Returns an immutable array containing the same values as this array. This is logically a no-op, and in some circumstances this itself is returned. However, if this instance is a subArray(int, int) view of a larger array, this method will copy only the appropriate range of values, resulting in an equivalent array with a smaller memory footprint.

Class ImmutableDoubleArray

Nested Class Summary

Method Summary

Methods inherited from class java.lang.Object

Method Detail

of

of

of

of

of

of

of

of

copyOf

copyOf

copyOf

copyOf

builder

builder

length

isEmpty

get

indexOf

lastIndexOf

contains

forEach

stream

toArray

subArray

asList

equals

hashCode

toString

trimmed