1 files changed, 111 insertions, 0 deletions
diff --git a/src/main/java/com/iciql/bytecode/Operation.java b/src/main/java/com/iciql/bytecode/Operation.java
new file mode 100644
index 0000000..7cd42d9
--- /dev/null
+++ b/src/main/java/com/iciql/bytecode/Operation.java
@@ -0,0 +1,111 @@
+/*
+ * Copyright 2004-2011 H2 Group.
+ * Copyright 2011 James Moger.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.iciql.bytecode;
+
+import com.iciql.Query;
+import com.iciql.SQLStatement;
+import com.iciql.Token;
+
+/**
+ * A mathematical or comparison operation.
+ */
+class Operation implements Token {
+
+	/**
+	 * The operation type.
+	 */
+	enum Type {
+		EQUALS("=") {
+			Type reverse() {
+				return NOT_EQUALS;
+			}
+		},
+		NOT_EQUALS("<>") {
+			Type reverse() {
+				return EQUALS;
+			}
+		},
+		BIGGER(">") {
+			Type reverse() {
+				return SMALLER_EQUALS;
+			}
+		},
+		BIGGER_EQUALS(">=") {
+			Type reverse() {
+				return SMALLER;
+			}
+		},
+		SMALLER_EQUALS("<=") {
+			Type reverse() {
+				return BIGGER;
+			}
+		},
+		SMALLER("<") {
+			Type reverse() {
+				return BIGGER_EQUALS;
+			}
+		},
+		ADD("+"), SUBTRACT("-"), MULTIPLY("*"), DIVIDE("/"), MOD("%");
+
+		private String name;
+
+		Type(String name) {
+			this.name = name;
+		}
+
+		public String toString() {
+			return name;
+		}
+
+		Type reverse() {
+			return null;
+		}
+
+	}
+
+	private final Token left, right;
+	private final Type op;
+
+	private Operation(Token left, Type op, Token right) {
+		this.left = left;
+		this.op = op;
+		this.right = right;
+	}
+
+	static Token get(Token left, Type op, Token right) {
+		if (op == Type.NOT_EQUALS && "0".equals(right.toString())) {
+			return left;
+		}
+		return new Operation(left, op, right);
+	}
+
+	public String toString() {
+		return left + " " + op + " " + right;
+	}
+
+	public Token reverse() {
+		return get(left, op.reverse(), right);
+	}
+
+	public <T> void appendSQL(SQLStatement stat, Query<T> query) {
+		left.appendSQL(stat, query);
+		stat.appendSQL(op.toString());
+		right.appendSQL(stat, query);
+	}
+
+}