Implement a few nodes for the pattern matching.

src/org/nwapw/abacus/lexing/pattern/AnyNode.java

@@ -0,0 +1,10 @@
+package org.nwapw.abacus.lexing.pattern;
+
+public class AnyNode<T> extends PatternNode<T> {
+
+    @Override
+    public boolean matches(char other) {
+        return true;
+    }
+
+}

src/org/nwapw/abacus/lexing/pattern/EndNode.java

@@ -0,0 +1,15 @@
+package org.nwapw.abacus.lexing.pattern;
+
+public class EndNode<T> extends PatternNode<T> {
+
+    private T patternId;
+
+    public EndNode(T patternId){
+        this.patternId = patternId;
+    }
+
+    public T getPatternId(){
+        return patternId;
+    }
+
+}

src/org/nwapw/abacus/lexing/pattern/LinkNode.java

@@ -0,0 +1,14 @@
+package org.nwapw.abacus.lexing.pattern;
+
+import java.util.ArrayList;
+
+public class LinkNode<T> extends PatternNode<T> {
+
+    @Override
+    public void addInto(ArrayList<PatternNode<T>> into) {
+        for(PatternNode<T> node : outputStates){
+            node.addInto(into);
+        }
+    }
+
+}

src/org/nwapw/abacus/lexing/pattern/PatternNode.java

@@ -0,0 +1,25 @@
+package org.nwapw.abacus.lexing.pattern;
+
+import java.util.ArrayList;
+
+public class PatternNode<T> {
+
+    protected ArrayList<PatternNode<T>> outputStates;
+
+    public PatternNode(){
+        outputStates = new ArrayList<>();
+    }
+
+    public boolean matches(char other){
+        return false;
+    }
+
+    public char range(){
+        return '\0';
+    }
+
+    public void addInto(ArrayList<PatternNode<T>> into){
+        into.add(this);
+    }
+
+}

src/org/nwapw/abacus/lexing/pattern/RangeNode.java

@@ -0,0 +1,18 @@
+package org.nwapw.abacus.lexing.pattern;
+
+public class RangeNode<T> extends PatternNode<T> {
+
+    private char from;
+    private char to;
+
+    public RangeNode(char from, char to){
+        this.from = from;
+        this.to = to;
+    }
+
+    @Override
+    public boolean matches(char other) {
+        return other >= from && other <= to;
+    }
+
+}

src/org/nwapw/abacus/lexing/pattern/ValueNode.java

@@ -0,0 +1,20 @@
+package org.nwapw.abacus.lexing.pattern;
+
+public class ValueNode<T> extends PatternNode<T> {
+
+    private char value;
+
+    public ValueNode(char value){
+        this.value = value;
+    }
+
+    @Override
+    public boolean matches(char other) {
+        return other == value;
+    }
+
+    @Override
+    public char range() {
+        return value;
+    }
+}