fix Issue2592

core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF16.java

@@ -73,6 +73,11 @@ class JSONReaderUTF16
                 }
                 ch = chars[this.offset];
             }
+
+            if (ch != '{') {
+                ch = EOI;
+                return;
+            }
             this.offset++;
         }
 
@@ -138,6 +143,11 @@ class JSONReaderUTF16
                 }
                 ch = chars[this.offset];
             }
+
+            if (ch != '{') {
+                ch = EOI;
+                return;
+            }
             this.offset++;
         }
 
@@ -184,6 +194,11 @@ class JSONReaderUTF16
                 }
                 ch = chars[this.offset];
             }
+
+            if (ch != '{') {
+                ch = EOI;
+                return;
+            }
             this.offset++;
         }
 
@@ -222,6 +237,10 @@ class JSONReaderUTF16
                 }
                 ch = chars[this.offset];
             }
+            if (ch != '{') {
+                ch = EOI;
+                return;
+            }
             this.offset++;
         }
 

core/src/main/java/com/alibaba/fastjson2/JSONReaderUTF8.java

@@ -450,6 +450,11 @@ public void next() {
             return;
         }
 
+        if (ch != '{') {
+            ch = EOI;
+            return;
+        }
+
         this.offset = offset;
         this.ch = (char) ch;
         if (ch == '/') {

core/src/test/java/com/alibaba/fastjson2/issues_2500/Issue2592.java

@@ -0,0 +1,120 @@
+package com.alibaba.fastjson2.issues_2500;
+
+import com.alibaba.fastjson2.JSON;
+import com.alibaba.fastjson2.JSONException;
+import com.alibaba.fastjson2.JSONObject;
+import com.alibaba.fastjson2.JSONReader;
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.StandardCharsets;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+public class Issue2592 {
+    String str = "\"name\":\"Huang\",\"minVersion\":\"1.1\",\"maxVersion\":\"1.2\"}";
+
+    @Test
+    void test() {
+        Exception error = null;
+        try {
+            JSONObject.parseObject(str, TestBean.class);
+        } catch (JSONException e) {
+            error = e;
+        }
+        assertNotNull(error);
+        assertTrue(error.getMessage().contains("illegal fieldName input"));
+    }
+
+    @Test
+    void testUTF8() {
+        byte[] utf8Bytes = str.getBytes(StandardCharsets.UTF_8);
+        Exception error = null;
+        try {
+            JSON.parseObject(utf8Bytes, TestBean.class);
+        } catch (JSONException e) {
+            error = e;
+        }
+        assertNotNull(error);
+        assertTrue(error.getMessage().contains("illegal fieldName input"));
+    }
+
+    @Test
+    void testUTF8Stream() {
+        ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(str.getBytes());
+        Exception error = null;
+        try {
+            JSON.parseObject(byteArrayInputStream, StandardCharsets.UTF_8);
+        } catch (JSONException e) {
+            error = e;
+        }
+        assertNotNull(error);
+    }
+
+    @Test
+    void testUTF8Stream2() {
+        ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(str.getBytes());
+        InputStreamReader inputStreamReader = new InputStreamReader(byteArrayInputStream);
+        JSONReader jsonReader = JSONReader.of(inputStreamReader);
+        Exception error = null;
+        try {
+            jsonReader.read(TestBean.class);
+        } catch (JSONException e) {
+            error = e;
+        }
+        assertNotNull(error);
+        assertTrue(error.getMessage().contains("illegal fieldName input"));
+    }
+
+    @Test
+    void testUTF16() {
+        String str1 = "\"name\": \"张三\", \"minVersion\": 30, \"maxVersion\": \"北京\" }";
+        byte[] utf16Bytes = str1.getBytes(StandardCharsets.UTF_16);
+        JSONReader jsonReader = JSONReader.of(utf16Bytes, 0, utf16Bytes.length, StandardCharsets.UTF_16);
+        Exception error = null;
+        try {
+            jsonReader.read(TestBean.class);
+        } catch (JSONException e) {
+            error = e;
+        }
+        assertNotNull(error);
+        assertTrue(error.getMessage().contains("illegal fieldName input"));
+    }
+    @Test
+    void testValid() {
+        boolean isValid = JSON.isValid(str);
+        assertFalse(isValid);
+    }
+
+    public static class TestBean {
+        String name;
+        String minVersion;
+        String maxVersion;
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public String getMinVersion() {
+            return minVersion;
+        }
+
+        public void setMinVersion(String minVersion) {
+            this.minVersion = minVersion;
+        }
+
+        public String getMaxVersion() {
+            return maxVersion;
+        }
+
+        public void setMaxVersion(String maxVersion) {
+            this.maxVersion = maxVersion;
+        }
+    }
+}