SpringBoot Filter修改返回内容,解决请求卡死200的错误

import org.springframework.stereotype.Component;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
/**
 * 过滤器
 */
@Component
@WebFilter(urlPatterns = "/*", filterName = "testFilter")
public class TestFilter implements Filter {
    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
        HSRW hsrw = new HSRW((HttpServletResponse) response);//获取返回内容
        filterChain.doFilter(request, hsrw);//一定要放到获取内容前面，否则会没有数据
        byte[] content = hsrw.getContent();//response流的内容
        String str = new String(content, StandardCharsets.UTF_8);
        System.out.println("原返回值:" + str);
        String newStr = "哈哈哈哈哈哈";
        //修改返回内容长度，解决返回内容长度不一致导致请求卡住的问题
        response.setContentLength(newStr.getBytes(StandardCharsets.UTF_8).length);//这里要注意：setContentLength(字符串的字节长度，不是字符串的长度)
        //修改完写入输出流，返回给前端
        //JDK8写法
        try (ServletOutputStream out = response.getOutputStream()) {
            out.write(newStr.getBytes(StandardCharsets.UTF_8));//写入返回内容
            out.flush();//刷新
        }
        //JDK8之前的写法
        /*ServletOutputStream out = response.getOutputStream();
        out.write(newStr.getBytes(StandardCharsets.UTF_8));//写入返回内容
        out.flush();//刷新
        out.close();//关闭流*/
    }
}

import javax.servlet.ServletOutputStream;
import javax.servlet.WriteListener;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;
import java.io.*;
public class HSRW extends HttpServletResponseWrapper {
    private final ByteArrayOutputStream buffer;
    private final ServletOutputStream out;
    public HSRW(HttpServletResponse httpServletResponse) {
        super(httpServletResponse);
        buffer = new ByteArrayOutputStream();
        out = new WrapperOutputStream(buffer);
    }
    @Override
    public ServletOutputStream getOutputStream() {
        return out;
    }
    @Override
    public void flushBuffer() throws IOException {
        if (out != null) {
            out.flush();
        }
    }
    public byte[] getContent() throws IOException {
        flushBuffer();
        return buffer.toByteArray();
    }
    static class WrapperOutputStream extends ServletOutputStream {
        private final ByteArrayOutputStream bos;
        public WrapperOutputStream(ByteArrayOutputStream bos) {
            this.bos = bos;
        }
        @Override
        public void write(int b) {
            bos.write(b);
        }
        @Override
        public boolean isReady() {
            return false;
        }
        @Override
        public void setWriteListener(WriteListener arg0) {
        }
    }
}

response.setContentLength(strChange.length());
ServletOutputStream out = response.getOutputStream();
out.write(strChange.getBytes());
out.flush();