diff --git a/sonar-keyware-plugins-java/src/main/java/com/keyware/sonar/java/rules/checkers/RedirectUrlChecker.java b/sonar-keyware-plugins-java/src/main/java/com/keyware/sonar/java/rules/checkers/RedirectUrlChecker.java
index 9069403..17bf995 100644
--- a/sonar-keyware-plugins-java/src/main/java/com/keyware/sonar/java/rules/checkers/RedirectUrlChecker.java
+++ b/sonar-keyware-plugins-java/src/main/java/com/keyware/sonar/java/rules/checkers/RedirectUrlChecker.java
@@ -2,8 +2,8 @@ package com.keyware.sonar.java.rules.checkers;
 
 import org.sonar.check.Rule;
 import org.sonar.java.ast.visitors.SubscriptionVisitor;
-import org.sonar.plugins.java.api.JavaFileScannerContext;
 import org.sonar.plugins.java.api.tree.*;
+import org.springframework.lang.NonNull;
 
 import java.util.Arrays;
 import java.util.List;
@@ -23,12 +23,12 @@ public class RedirectUrlChecker extends SubscriptionVisitor {
     }
 
     @Override
-    public void visitNode(Tree tree) {
+    public void visitNode(@NonNull Tree tree) {
         MethodTree methodTree = (MethodTree) tree;
         BlockTree block = methodTree.block();
         // 方法的参数列表
         List<? extends VariableTree> parameters = methodTree.parameters();
-        if (block != null && !parameters.isEmpty() && isHttpRequestHandlerMethod(methodTree)) {
+        if (block != null && !parameters.isEmpty() && isHttpRequestHandlerMethod(methodTree) && methodTree.returnType() != null) {
             // 判断方法的返回节点的类型为RedirectView 或 String 类型
             if ("RedirectView".equals(methodTree.returnType().toString())) {
                 // 传递上下文，和方法的参数列表
@@ -40,14 +40,14 @@ public class RedirectUrlChecker extends SubscriptionVisitor {
     }
 
     private void checkByStringType(BlockTree block, List<? extends VariableTree> methodParameters) {
-        for (StatementTree statementTree : block.body()){
-            if(statementTree.kind() == Tree.Kind.RETURN_STATEMENT){
+        for (StatementTree statementTree : block.body()) {
+            if (statementTree.kind() == Tree.Kind.RETURN_STATEMENT) {
                 ReturnStatementTree rs = (ReturnStatementTree) statementTree;
                 ExpressionTree exprTree = rs.expression();
-                if(exprTree != null && !exprTree.is(Tree.Kind.STRING_LITERAL)){
-                    if(exprTree instanceof BinaryExpressionTree){
+                if (exprTree != null && !exprTree.is(Tree.Kind.STRING_LITERAL)) {
+                    if (exprTree instanceof BinaryExpressionTree) {
                         BinaryExpressionTree bExprTree = (BinaryExpressionTree) exprTree;
-                        if(bExprTree.is(Tree.Kind.PLUS) && bExprTree.leftOperand().is(Tree.Kind.STRING_LITERAL) && bExprTree.rightOperand().is(Tree.Kind.IDENTIFIER)){
+                        if (bExprTree.is(Tree.Kind.PLUS) && bExprTree.leftOperand().is(Tree.Kind.STRING_LITERAL) && bExprTree.rightOperand().is(Tree.Kind.IDENTIFIER)) {
                             var identifierTree = (IdentifierTree) bExprTree.rightOperand();
                             String argName = identifierTree.name();
                             if (methodParameters.stream().anyMatch(parameter -> parameter.simpleName().name().equals(argName))) {