final version

5 files changed, 70 insertions, 9 deletions

diff --git a/src/minijava/symboltable/MClasses.java b/src/minijava/symboltable/MClasses.java
index 10bd009..34601a5 100644
--- a/src/minijava/symboltable/MClasses.java
+++ b/src/minijava/symboltable/MClasses.java
@@ -46,6 +46,9 @@ public class MClasses extends MType {
 			String ext_name = m_class.extend_class_name;
 			if (ext_name!=null) {
 				m_class.extend_class = findClassByName(ext_name);
+				if (m_class.extend_class==null) {
+					PrintError.print(m_class.line, m_class.column, "Extend class not exist!");
+				}
 			}
 		}
 		int tag = 1; // 扫描循环继承的标记
diff --git a/src/minijava/symboltable/MExpression.java b/src/minijava/symboltable/MExpression.java
index 4cf4724..a5dc0ba 100644
--- a/src/minijava/symboltable/MExpression.java
+++ b/src/minijava/symboltable/MExpression.java
@@ -76,7 +76,15 @@ public class MExpression extends MType {
 				PrintError.print(line, column, "no class found in a message send expression");
 				return null;
 			}
-			int idx = m_class.methods.findMethod(e_id.name);
+			int idx=-1;
+			while (m_class!=null) {
+				idx = m_class.methods.findMethod(e_id.name);
+				if (idx==-1) {
+					m_class = m_class.extend_class; // 本类无该方法，从父类继续找
+				} else {
+					break;
+				}
+			}
 			if (idx==-1) {
 				PrintError.print(line, column, "method " + e_id.name + " not found");
 				return null;
@@ -141,6 +149,13 @@ public class MExpression extends MType {
 			System.err.print("]");
 		case ArrayLen:
 		case MsgSend:
+			first.printExpr(0);
+			System.err.print("."+e_id.name+"(");
+			for (int i=0; i<e_list.size(); i++) {
+				if (i>0) System.err.print(",");
+				e_list.e_list.elementAt(i).printExpr(0);
+			}
+			System.err.print(")");
 		}
 	}
 }
diff --git a/src/minijava/symboltable/MMethod.java b/src/minijava/symboltable/MMethod.java
index 2d2dc24..9e770a3 100644
--- a/src/minijava/symboltable/MMethod.java
+++ b/src/minijava/symboltable/MMethod.java
@@ -4,7 +4,7 @@ import minijava.typecheck.PrintError;
 
 public class MMethod extends MLocalVarType {
 	MVarList params;
-	String ret_type_name;
+	public String ret_type_name;
 	public MClass method_class;
 	MVarList paramList;
 	public MStatementList statements;
@@ -74,9 +74,10 @@ public class MMethod extends MLocalVarType {
 			if (idx!=-1) {
 				// 找到同名方法，检测是否能覆盖
 				if (this.ret_type_name.
-						equals(m_class.methods.methods.elementAt(idx))==false) {
+						equals(m_class.methods.methods.elementAt(idx).ret_type_name)==false) {
 					PrintError.print(line, column, "Method " +
-						this.name + " has type different from the one in its parent class");
+						this.name + " has type different from the one in its parent class "
+						+ m_class.name);
 					return false;
 				}
 			}
@@ -95,15 +96,37 @@ public class MMethod extends MLocalVarType {
 		if (idx!=-1) {
 			return paramList.varlist.elementAt(idx);
 		}
-		idx = method_class.vars.findVar(s);
+		MClass m_class = method_class;
+		idx = m_class.vars.findVar(s);		
+		while (idx==-1 && m_class.extend_class!=null) {
+			// 在父类继续查找
+			m_class = m_class.extend_class;
+			idx = m_class.vars.findVar(s);
+		}
 		if (idx!=-1) {
-			return method_class.vars.varlist.elementAt(idx);
+			return m_class.vars.varlist.elementAt(idx);
 		}
 		return null;
 	}
 	
 	public void checkStatements() {
 		statements.checkStatements(this);
+		// 检查返回类型是否和返回值匹配
+		if (ret_type_name==MIdentifier.voidType && ret_expr==null) {
+			// ok
+		} else if (!ret_type_name.equals(ret_expr.exprType(this))) {
+			MClasses all = this.method_class.all_classes;
+			MClass t1 = all.findClassByName(ret_type_name);
+			MClass t2 = all.findClassByName(ret_expr.exprType(this));
+			if (t1!=null) {
+				while (t2!=null && t2!=t1) {
+					t2 = t2.extend_class;
+				}
+			}
+			if (t1!=t2) {
+				PrintError.print(line, column, "return expression and return type mismatch!");
+			}
+		}
 	}
 	
 	public void printMethod(int spaces) {
diff --git a/src/minijava/symboltable/MPrimaryExpr.java b/src/minijava/symboltable/MPrimaryExpr.java
index ba233b5..246ac93 100644
--- a/src/minijava/symboltable/MPrimaryExpr.java
+++ b/src/minijava/symboltable/MPrimaryExpr.java
@@ -44,6 +44,10 @@ public class MPrimaryExpr extends MType {
 		case Alloc:
 			return e_id.getName();
 		case ArrayAlloc:
+			if (e_exp.exprType(m)!=MIdentifier.intType) {
+				PrintError.print(getLine(), getColumn(), "wrong type of expression in array alloc");
+				return null;
+			}
 			return MIdentifier.arrType;
 		case Braket:
 			return e_exp.exprType(m);
diff --git a/src/minijava/symboltable/MStatement.java b/src/minijava/symboltable/MStatement.java
index 3610719..5169097 100644
--- a/src/minijava/symboltable/MStatement.java
+++ b/src/minijava/symboltable/MStatement.java
@@ -36,13 +36,29 @@ public class MStatement extends MType {
 		case Assign:
 			// id = expr
 			MVariable m_var = m.findVarByName(s_id.name);
+			String expr_type = e_first.exprType(m);
+			//System.err.println(s_id.name + " " + expr_type);
 			if (m_var==null) {
 				PrintError.print(line, column, "variable "+s_id.name+" not exist!");
 				return;
-			} else if (m_var.typename.equals(e_first.exprType(m))) {
+			} else if (m_var.typename.equals(expr_type)) {
 				return;
 			} else {
-				PrintError.print(line, column, "type mismatch in assign statement");
+				MClasses all = m.method_class.all_classes;
+				MClass id_class = all.findClassByName(m_var.typename);
+				MClass expr_class = all.findClassByName(expr_type);
+				if (id_class==null) { // id本身不是类
+					PrintError.print(line, column, "type mismatch in assign statement");
+					return;
+				}
+				while (expr_class!=id_class && expr_class!=null) { // 从expr的类找父类
+					expr_class = expr_class.extend_class;
+				}
+				if (expr_class!=id_class) {
+					PrintError.print(line, column, "type mismatch in assign statement");
+				} else {
+					return;
+				}
 			}
 			break;
 		case Block:
@@ -57,7 +73,7 @@ public class MStatement extends MType {
 			}
 			break;
 		case Print:
-			if (e_first.exprType(m)!=null) {
+			if (e_first.exprType(m)==MIdentifier.intType) {
 				return;
 			} else {
 				PrintError.print(line, column, "Invalid type in print statement");