1 files changed, 70 insertions, 1 deletions

diff --git a/src/minijava/symboltable/MMethod.java b/src/minijava/symboltable/MMethod.java
index 7f57a40..2d2dc24 100644
--- a/src/minijava/symboltable/MMethod.java
+++ b/src/minijava/symboltable/MMethod.java
@@ -1,9 +1,11 @@
 package minijava.symboltable;
 
+import minijava.typecheck.PrintError;
+
 public class MMethod extends MLocalVarType {
 	MVarList params;
 	String ret_type_name;
-	MClass method_class;
+	public MClass method_class;
 	MVarList paramList;
 	public MStatementList statements;
 	public MExpression ret_expr;
@@ -37,6 +39,73 @@ public class MMethod extends MLocalVarType {
 		return null;
 	}
 	
+	// 检测函数的返回类型，参数类型，局部变量类型是否为有效类型
+	public boolean validVars() {
+		if (method_class.validType(ret_type_name)==false) {
+			PrintError.print(this.line, this.column, "Return type of method "+this.name+" invalid");
+			return false;
+		}
+		
+		for (int i=0; i<paramList.size(); i++) {
+			MVariable p_var = paramList.varlist.elementAt(i);
+			if (method_class.validType(p_var.typename)==false) {
+				PrintError.print(p_var.line, p_var.column, "Type "+p_var.typename+" invalid");
+				return false;
+			}
+		}
+		
+		for (int i=0; i<vars.size(); i++) {
+			MVariable m_var = vars.varlist.elementAt(i);
+			if (method_class.validType(m_var.typename)==false) {
+				PrintError.print(m_var.line, m_var.column, "Type "+m_var.typename+" invalid");
+				return false;
+			}
+		}
+		
+		return true;
+	}
+	
+	// 检查方法自身是否复合方法覆盖条件
+	public boolean validFunc() {
+		MClass m_class = method_class;
+		while (m_class.extend_class!=null) {
+			m_class = m_class.extend_class;
+			int idx = m_class.methods.findMethod(this.name);
+			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) {
+					PrintError.print(line, column, "Method " +
+						this.name + " has type different from the one in its parent class");
+					return false;
+				}
+			}
+		}
+		return true;
+	}
+	
+	// 从局部变量，参数表，类变量中查找变量
+	public MVariable findVarByName(String s) {
+		int idx;
+		idx = vars.findVar(s);
+		if (idx!=-1) {
+			return vars.varlist.elementAt(idx);
+		}
+		idx = paramList.findVar(s);
+		if (idx!=-1) {
+			return paramList.varlist.elementAt(idx);
+		}
+		idx = method_class.vars.findVar(s);
+		if (idx!=-1) {
+			return method_class.vars.varlist.elementAt(idx);
+		}
+		return null;
+	}
+	
+	public void checkStatements() {
+		statements.checkStatements(this);
+	}
+	
 	public void printMethod(int spaces) {
 		String ps = OutputFormat.spaces(spaces);
 		System.err.print(ps + this.ret_type_name + " " + this.name + "(");