支持Long超过一定长度自动转字符串，解决js精度丢失问题

src/main/java/com/cool/core/config/BigNumberSerializer.java

@@ -0,0 +1,40 @@
+package com.cool.core.config;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.fasterxml.jackson.databind.SerializerProvider;
+import com.fasterxml.jackson.databind.annotation.JacksonStdImpl;
+import com.fasterxml.jackson.databind.ser.std.NumberSerializer;
+
+import java.io.IOException;
+
+/**
+ * 超出 JS 最大最小值 处理
+ */
+@JacksonStdImpl
+public class BigNumberSerializer extends NumberSerializer {
+
+    /**
+     * 根据 JS Number.MAX_SAFE_INTEGER 与 Number.MIN_SAFE_INTEGER 得来
+     */
+    private static final long MAX_SAFE_INTEGER = 9007199254740991L;
+    private static final long MIN_SAFE_INTEGER = -9007199254740991L;
+
+    /**
+     * 提供实例
+     */
+    public static final BigNumberSerializer INSTANCE = new BigNumberSerializer(Number.class);
+
+    public BigNumberSerializer(Class<? extends Number> rawType) {
+        super(rawType);
+    }
+
+    @Override
+    public void serialize(Number value, JsonGenerator gen, SerializerProvider provider) throws IOException {
+        // 超出范围 序列化位字符串
+        if (value.longValue() > MIN_SAFE_INTEGER && value.longValue() < MAX_SAFE_INTEGER) {
+            super.serialize(value, gen, provider);
+        } else {
+            gen.writeString(value.toString());
+        }
+    }
+}

src/main/java/com/cool/core/config/JacksonConfig.java

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+package com.cool.core.config;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.module.SimpleModule;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
+import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
+
+import java.math.BigInteger;
+
+@Configuration
+public class JacksonConfig {
+
+    @Bean
+    public MappingJackson2HttpMessageConverter jackson2HttpMessageConverter() {
+        final Jackson2ObjectMapperBuilder builder = new Jackson2ObjectMapperBuilder();
+        final ObjectMapper objectMapper = builder.build();
+        SimpleModule simpleModule = new SimpleModule();
+        // Long,BigInteger 转为 String 防止 js 丢失精度
+        simpleModule.addSerializer(Long.class, BigNumberSerializer.INSTANCE);
+        simpleModule.addSerializer(Long.TYPE, BigNumberSerializer.INSTANCE);
+        simpleModule.addSerializer(BigInteger.class, BigNumberSerializer.INSTANCE);
+        objectMapper.registerModule(simpleModule);
+
+        return new MappingJackson2HttpMessageConverter(objectMapper);
+    }
+}