initial version

1 files changed, 92 insertions, 0 deletions

diff --git a/src/uk/ac/ox/cs/pagoda/query/AnswerTuplesImp.java b/src/uk/ac/ox/cs/pagoda/query/AnswerTuplesImp.java
new file mode 100644
index 0000000..3e0f320
--- /dev/null
+++ b/src/uk/ac/ox/cs/pagoda/query/AnswerTuplesImp.java
@@ -0,0 +1,92 @@
+package uk.ac.ox.cs.pagoda.query;
+
+import java.util.Iterator;
+import java.util.Set;
+
+public class AnswerTuplesImp implements AnswerTuples {
+
+        int m_index; 
+        Iterator<AnswerTuple> m_iter;
+        Set<AnswerTuple> m_answers1, m_answers2; 
+        String[] m_answerVars; 
+        AnswerTuple m_tuple; 
+
+        public AnswerTuplesImp(String[] answerVars, Set<AnswerTuple> answers) {
+                m_answers1 = answers;
+                m_answers2 = null; 
+                m_answerVars = answerVars; 
+                reset(); 
+        }
+        
+        public AnswerTuplesImp(String[] answerVars, Set<AnswerTuple> answers1, Set<AnswerTuple> answers2) {
+                m_answers1 = answers1; 
+                m_answers2 = answers2; 
+                m_answerVars = answerVars; 
+                reset(); 
+        }
+        
+        @Override
+        public boolean isValid() {
+                return m_tuple != null; 
+        }
+
+        @Override
+        public int getArity() {
+                return m_answerVars.length;
+        }
+
+        @Override
+        public void moveNext() {
+                if (m_iter != null && m_iter.hasNext()) {
+                        m_tuple = m_iter.next();
+                        return ; 
+                }
+                else if (m_answers2 != null && m_index == 1){
+                        ++m_index; 
+                        m_iter = m_answers2.iterator(); 
+                        if (m_iter.hasNext()) {
+                                m_tuple = m_iter.next();
+                                return ; 
+                        }
+                }
+                else
+                        m_tuple = null; 
+        }
+
+        @Override
+        public void dispose() {}
+
+        @Override
+        public void reset() {
+                if (m_answers1 == null || m_answers1.isEmpty()) {
+                        m_index = 2;
+                        m_iter = m_answers2 == null ? null : m_answers2.iterator();
+                }
+                else {
+                        m_index = 1; 
+                        m_iter =  m_answers1.iterator();
+                }               
+                moveNext();
+        }
+
+        @Override
+        public boolean contains(AnswerTuple t) {
+                return m_answers1.contains(t) || (m_answers2 != null && m_answers2.contains(t));
+        }
+
+        @Override
+        public AnswerTuple getTuple() {
+                return m_tuple; 
+        }
+
+        @Override
+        public String[] getAnswerVariables() {
+                return m_answerVars;
+        }
+
+        @Override
+        public void remove() {
+                m_iter.remove();
+        }
+
+}