diff --git a/AlgebraicDataflowArchitectureModel/src/code/ast/Constant.java b/AlgebraicDataflowArchitectureModel/src/code/ast/Constant.java
new file mode 100644
index 0000000..f15c136
--- /dev/null
+++ b/AlgebraicDataflowArchitectureModel/src/code/ast/Constant.java
@@ -0,0 +1,27 @@
+package code.ast;
+
+/**
+ * Represents a constant in the AST (Abstract Syntax Tree)
+ *
+ * @author s-yamagiwa
+ */
+public class Constant extends Expression {
+	private String value;
+	
+	public Constant(String value) {
+		this.value = value;
+	}
+	
+	public String getValue() {
+		return value;
+	}
+	
+	public void setValue(String value) {
+		this.value = value;
+	}
+	
+	@Override
+	public String toString() {
+		return value;
+	}
+}
diff --git a/AlgebraicDataflowArchitectureModel/src/code/ast/Variable.java b/AlgebraicDataflowArchitectureModel/src/code/ast/Variable.java
new file mode 100644
index 0000000..6d3dc00
--- /dev/null
+++ b/AlgebraicDataflowArchitectureModel/src/code/ast/Variable.java
@@ -0,0 +1,27 @@
+package code.ast;
+
+/**
+ * Represents a variable in the AST (Abstract Syntax Tree)
+ *
+ * @author s-yamagiwa
+ */
+public class Variable extends Expression {
+	private String name;
+	
+	public Variable(String name) {
+		this.name = name;
+	}
+	
+	public String getName() {
+		return name;
+	}
+	
+	public void setName(String name) {
+		this.name = name;
+	}
+	
+	@Override
+	public String toString() {
+		return name;
+	}
+}