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package jaggregate; |
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import java.util.NoSuchElementException; |
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import static jaggregate.OrderedCollection.*; |
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import static jaggregate.internal.ArgumentChecks.*; |
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29 | 0 | public class ReadStream<E> extends CollectionStream<E, ReadOnlySequence<E>> |
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implements GettableStream<E, ReadOnlySequence<E>> { |
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public ReadStream( ReadOnlySequence<E> backingStore ) { |
39 | 206 | super( backingStore ); |
40 | 205 | } |
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public static <T> ReadStream<T> readStreamOver( ReadOnlySequence<T> backingStore ) { |
51 | 206 | return new ReadStream<T>( backingStore ); |
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} |
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public <R> void forEachDo( UnaryFunctor<? super E, ? extends R> operation ) { |
58 | 16 | ensureOpen(); |
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60 | 33 | while ( !atEnd() ) |
61 | 19 | operation.evaluate( next() ); |
62 | 14 | } |
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public E next() { |
68 | 143 | ensureOpen(); |
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70 | 142 | if ( atEnd() ) |
71 | 6 | throw new NoSuchElementException( "no more elements in the stream" ); |
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73 | 136 | E result = contents().at( position() ); |
74 | 136 | advance(); |
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76 | 136 | return result; |
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} |
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public OrderedCollection<E> next( int amount ) { |
83 | 24 | ensureOpen(); |
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85 | 23 | if ( amount < 0 ) |
86 | 1 | throw new IllegalArgumentException( NEGATIVE_AMOUNT + amount ); |
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88 | 22 | int numberOfNextElements = maxPosition() - position(); |
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90 | 22 | if ( amount > numberOfNextElements ) |
91 | 9 | throw new IllegalArgumentException( |
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"there are not " |
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+ amount |
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+ " elements left in the stream, only " |
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+ numberOfNextElements ); |
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97 | 13 | OrderedCollection<E> nextElements = emptyOrderedCollection(); |
98 | 26 | for ( int i = 0; i < amount; ++i ) |
99 | 13 | nextElements.add( next() ); |
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101 | 13 | return nextElements; |
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} |
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public boolean isNextMatchFor( E target ) { |
108 | 12 | ensureOpen(); |
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110 | 11 | return Objects.areEqual( target, next() ); |
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} |
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public E peek() { |
117 | 35 | ensureOpen(); |
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119 | 34 | return atEnd() ? null : contents().at( position() ); |
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} |
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public boolean isPeekMatchFor( E target ) { |
126 | 23 | ensureOpen(); |
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128 | 22 | return Objects.areEqual( target, peek() ); |
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} |
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public void skip( int amount ) { |
135 | 15 | ensureOpen(); |
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137 | 14 | if ( amount < 0 ) |
138 | 1 | throw new IllegalArgumentException( NEGATIVE_AMOUNT + amount ); |
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140 | 13 | int newPosition = position() + amount; |
141 | 13 | if ( newPosition >= maxPosition() ) |
142 | 9 | setToEnd(); |
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else |
144 | 4 | position( newPosition ); |
145 | 13 | } |
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public boolean skipTo( E target ) { |
151 | 15 | ensureOpen(); |
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153 | 32 | while ( !atEnd() ) { |
154 | 26 | if ( Objects.areEqual( target, next() ) ) |
155 | 8 | return true; |
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} |
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158 | 6 | return false; |
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} |
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public OrderedCollection<E> upTo( E target ) { |
165 | 28 | ensureOpen(); |
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167 | 28 | OrderedCollection<E> results = emptyOrderedCollection(); |
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169 | 66 | while ( !atEnd() ) { |
170 | 56 | E nextItem = next(); |
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172 | 56 | if ( Objects.areEqual( target, nextItem ) ) |
173 | 18 | return results; |
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175 | 38 | results.add( nextItem ); |
176 | 38 | } |
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178 | 10 | return results; |
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} |
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} |