School Commit Init

Anul 2/Semestrul 1/Metode avansate de programare/Interpretor/Models/Statements/WhileStatement.java

@@ -0,0 +1,58 @@
+package Models.Statements;
+
+import Exceptions.BaseException;
+import Models.Expressions.IExpression;
+import Models.Program.IDictionary;
+import Models.Program.IHeap;
+import Models.Program.IStack;
+import Models.Program.ProgramState;
+import Models.Types.BooleanType;
+import Models.Types.IType;
+import Models.Values.IValue;
+import Models.Values.BooleanValue;
+
+public class WhileStatement implements IStatement {
+    private IStatement statement;
+    private IExpression expression;
+
+    public WhileStatement(IStatement statement, IExpression expression) {
+        this.statement = statement;
+        this.expression = expression;
+    }
+
+    public ProgramState execute(ProgramState state) throws BaseException {
+        IStack<IStatement> stack = state.getStack();
+        IHeap heap = state.getHeap();
+        IDictionary<String, IValue> symbolTable = state.getSymbolTable();
+
+        IValue condition = expression.evaluate(symbolTable, heap);
+        if (!condition.getType().equals(new BooleanType())) {
+            throw new BaseException("Condition is not a boolean.");
+        }
+
+        if (((BooleanValue) condition).getValue()) {
+            stack.push(this);
+            stack.push(statement);
+        }
+
+        return null;
+    }
+
+    public String toString() {
+        return "while(" + expression.toString() + ") {" + statement.toString() + "}";
+    }
+
+    public IStatement copy() {
+        return new WhileStatement(statement.copy(), expression.copy());
+    }
+
+    public IDictionary<String, IType> typeCheck(IDictionary<String, IType> typeTable) throws BaseException {
+        IType expressionType = expression.typeCheck(typeTable);
+        if (expressionType.equals(new BooleanType())) {
+            statement.typeCheck(typeTable.copy());
+            return typeTable;
+        } else {
+            throw new BaseException("Condition is not a boolean!");
+        }
+    }
+}