RestTemplate自定义ErrorHandler方式

                Object varl4;
                // 1 创建请求，获取响应
                ClientHttpRequest request = this.createRequest(url, method);
                if (requestCallback != null) {
                    requestCallback.doWithRequest(request);
                }
                response = request.execute();
 
                // 2 判断响应是否存在异常，处理异常
                this.handleResponse(url, method, response);
 
                // 3 将响应消息体封装为java对象
                if (responseExtractor == null) {
                   resource = null;
                   return resource;
                }
                var14 = responseExtractor.extractData(response);

    protected void handleResponse(URI url, HttpMethod method, ClientHttpResponse response) throws ioException {
        ResponseErrorHandler errorHandler = this.getErrorHandler();
        boolean hasError = errorHandler.hasError(response);
        if (this.logger.isDebugEnabled()) {
            try {
                this.logger.debug(method.name() + " request for \"" + url + "\" resulted in " + response.getRawStatusCode() + " (" + response.getStatusText() + ")" + (hasError ? "; invoking error handler" : ""));
            } catch (IOException var7) {
                ;
            }
        }
        if (hasError) {
            errorHandler.handleError(url, method, response);
        }
    }

public class MyException extends RuntimeException { 
    public MyException(String message){
        super(message);
    } 
    public MyException(String message, Throwable e){
        super(message + e.getLocalizedMessage());
    }
}

public class MyErrorHandler extends DefaultResponseErrorHandler { 
    @Override
     public boolean hasError(ClientHttpResponse response) throws IOException{
        return super.hasError(response);
    }
 
    @Override
    public void handleError(ClientHttpResponse response) throws IOException{
        Scanner scanner = new Scanner(response.getBody()).useDelimiter("\\A");
        String stringResponse = scanner.hasNext() ? scanner.next() : "";
        if(stringResponse.matches(".*XXX.*")){
            throw new MyException(stringResponse);
        }
        else{
            super.handleError(response);
        }
    }
}

public class RestTemplate extends InterceptingHttpAccessor implements RestOperations { 
    private ResponseErrorHandler errorHandler;
    ......    
    @Nullable
    protected <T> T doExecute(URI url, @Nullable HttpMethod method, @Nullable RequestCallback requestCallback, @Nullable ResponseExtractor<T> responseExtractor) throws RestClientException {
        Assert.notNull(url, "'url' must not be null");
        Assert.notNull(method, "'method' must not be null");
        ClientHttpResponse response = null; 
        String resource;
        try {
            ClientHttpRequest request = this.createRequest(url, method);
            if (requestCallback != null) {
                requestCallback.doWithRequest(request);
            }
 
            response = request.execute();
            // 处理 Response
            this.handleResponse(url, method, response);
            if (responseExtractor != null) {
                Object var14 = responseExtractor.extractData(response);
                return var14;
            }
 
            resource = null;
        } catch (IOException var12) {
            resource = url.toString();
            String query = url.getRawQuery();
            resource = query != null ? resource.substring(0, resource.indexOf(63)) : resource;
            throw new ResourceAccessException("I/O error on " + method.name() + " request for \"" + resource + "\": " + var12.getMessage(), var12);
        } finally {
            if (response != null) {
                response.close();
            } 
        } 
        return resource;
    } 
    protected void handleResponse(URI url, HttpMethod method, ClientHttpResponse response) throws IOException {
        ResponseErrorHandler errorHandler = this.getErrorHandler();
        boolean hasError = errorHandler.hasError(response);
        if (this.logger.isDebugEnabled()) {
            try {
                this.logger.debug(method.name() + " request for \"" + url + "\" resulted in " + response.getRawStatusCode() + " (" + response.getStatusText() + ")" + (hasError ? "; invoking error handler" : ""));
            } catch (IOException var7) {
                ;
            }
        }
        // 异常处理
        if (hasError) {
            errorHandler.handleError(url, method, response);
        } 
    }
}

public class DefaultResponseErrorHandler implements ResponseErrorHandler {
    ...    
    protected void handleError(ClientHttpResponse response, httpstatus statusCode) throws IOException {
        switch(statusCode.series()) {
        case CLIENT_ERROR:
            throw new HttpClientErrorException(statusCode, response.getStatusText(), response.getHeaders(), this.getResponseBody(response), this.getCharset(response));
        case SERVER_ERROR:
            throw new HttpServerErrorException(statusCode, response.getStatusText(), response.getHeaders(), this.getResponseBody(response), this.getCharset(response));
        default:
            throw new UnknownHttpStatusCodeException(statusCode.value(), response.getStatusText(), response.getHeaders(), this.getResponseBody(response), this.getCharset(response));
        }
    }
}

public interface ResponseErrorHandler {
 
    // 标示 Response 是否存在任何错误。实现类通常会检查 Response 的 HttpStatus。
    boolean hasError(ClientHttpResponse var1) throws IOException;
 
    // 处理 Response 中的错误, 当 HasError 返回 true 时才调用此方法。
    void handleError(ClientHttpResponse var1) throws IOException;
 
    // handleError 的替代方案，提供访问请求URL和HTTP方法的额外信息。
    default void handleError(URI url, HttpMethod method, ClientHttpResponse response) throws IOException {
        this.handleError(response);
    }
}

public class CustomErrorHandler implements ResponseErrorHandler { 
    @Override
    public boolean hasError(ClientHttpResponse response) throws IOException {
        return true;
    } 
    @Override
    public void handleError(ClientHttpResponse response) throws IOException {
 
    }
}

restTemplate.setErrorHandler(new CustomErrorHandler());
ResponseEntity<String> response = restTemplate.exchange(uri, HttpMethod.GET, null, String.class);
System.out.println(response.getBody());