LoginSignup
19

More than 3 years have passed since last update.

RestTemplate による HTTP 通信の際に発生する様々なエラー (例外) を処理する

Last updated at Posted at 2019-07-24

概要

  • Spring Framework の RestTemplate クラスを利用して HTTP 通信をする
  • サンプルプログラムを実行して HTTP 通信の際に発生する様々な例外を確認する

例外クラス RestClientException の継承関係ツリー

Spring Framework のドキュメントを見ると、RestTemplate は org.springframework.web.client.RestClientException を投げることが記載されている。
例外を catch して中身を確認すると、実際には RestClientException のサブクラスが throw されているのがわかる。

  • RestClientException (RestTemplate が投げる例外のベースとなるクラス)
    • RestClientResponseException (HTTPレスポンスデータを含む例外のベースとなるクラス)
      • HttpStatusCodeException (ステータスコードに基づく例外の抽象クラス)
        • HttpClientErrorException (HTTP 4xx系を受信したとき)
          • 4xx系ステータスコードのそれぞれの例外クラス(複数)
        • HttpServerErrorException (HTTP 5xx系を受信したとき)
          • 5xx系ステータスコードのそれぞれの例外クラス(複数)
      • UnknownHttpStatusCodeException (不明なステータスコードのとき)
    • ResourceAccessException (I/Oエラーが発生したとき)

サンプルプログラムで発生した例外の一覧

HTTP 404 Not Found の場合

  • 発生した例外: org.springframework.web.client.HttpClientErrorException$NotFound
  • HttpClientErrorException.NotFound は org.springframework.web.client.HttpClientErrorException のサブクラス

HTTP 500 Internal Server Error の場合

  • 発生した例外: org.springframework.web.client.HttpServerErrorException$InternalServerError
  • HttpServerErrorException.InternalServerError は org.springframework.web.client.HttpServerErrorException のサブクラス

不明なステータスコードの場合

  • 発生した例外: org.springframework.web.client.UnknownHttpStatusCodeException

URL文字列ではない場合

  • 発生した例外: java.lang.IllegalArgumentException

URL文字列として解析できない場合

  • 発生した例外: java.net.URISyntaxException

URLのスキーム名が不明の場合

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: java.net.MalformedURLException

ホスト名からIPアドレスが引けない場合

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: java.net.UnknownHostException

Webサーバが起動していないポートへアクセスした場合 (Connection refused)

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: java.net.ConnectException

信頼できないSSLサーバ証明書 (自己署名証明書, オレオレ証明書) の場合

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: javax.net.ssl.SSLHandshakeException

接続タイムアウト (Connection Timeout) の場合 (マシンが存在しないIPアドレスなど)

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: java.net.SocketTimeoutException

読み取りタイムアウト (Read Timeout) の場合

  • 発生した例外: org.springframework.web.client.ResourceAccessException
  • 原因となる例外: java.net.SocketTimeoutException

動作確認環境

  • macOS Mojave
  • OpenJDK 11.0.2
  • Spring Framework 5.1.8

サンプルプログラムのソースコード

ソースコード一覧

├── pom.xml
└── src
    └── main
        └── java
            └── com
                └── example
                    └── MyHttpClient.java

Maven のビルド用ファイル pom.xml

今回はサンプルプログラムを Maven でビルドする。
RestTemplate クラスは Spring Framework の Spring Web に含まれているため、dependencies に spring-web を追加する。

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">

  <modelVersion>4.0.0</modelVersion>

  <groupId>com.example</groupId>
  <artifactId>my-http-client</artifactId>
  <version>1.0-SNAPSHOT</version>

  <properties>
    <maven.compiler.source>11</maven.compiler.source>
    <maven.compiler.target>11</maven.compiler.target>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <build>
    <plugins>
      <!-- http://maven.apache.org/plugins/maven-assembly-plugin/ -->
      <plugin>
        <artifactId>maven-assembly-plugin</artifactId>
        <version>3.1.1</version>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>single</goal>
            </goals>
          </execution>
        </executions>
        <configuration>
          <descriptorRefs>
            <descriptorRef>jar-with-dependencies</descriptorRef>
          </descriptorRefs>
          <archive>
            <manifest>
              <mainClass>com.example.MyHttpClient</mainClass>
            </manifest>
          </archive>
        </configuration>
      </plugin>
    </plugins>
  </build>

  <dependencies>
    <!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>5.1.8.RELEASE</version>
    </dependency>
  </dependencies>

</project>

MyHttpClient.java

HTTP 通信の際に発生する様々な例外を確認するためのクラス。

package com.example;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.RequestEntity;
import org.springframework.http.ResponseEntity;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.web.client.ResourceAccessException;
import org.springframework.web.client.RestClientException;
import org.springframework.web.client.RestClientResponseException;
import org.springframework.web.client.RestTemplate;

import java.net.URI;
import java.net.URISyntaxException;

public class MyHttpClient {

  public static void main(String[] args) {

    RestTemplate restTemplate = new RestTemplate();

    // タイムアウト値を設定
    if(restTemplate.getRequestFactory() instanceof SimpleClientHttpRequestFactory) {
      SimpleClientHttpRequestFactory rf = (SimpleClientHttpRequestFactory)restTemplate.getRequestFactory();
      rf.setConnectTimeout(1000); // 接続タイムアウトを1000ミリ秒に設定
      rf.setReadTimeout(1000); // 読み取りタイムアウトを1000ミリ秒に設定
    }

    // RestTemplate が内部で使用している ClientHttpRequestFactory のクラス名を出力
    System.out.println("ClientHttpRequestFactory: " + restTemplate.getRequestFactory().getClass().getName());

    // いろいろなパターンを試す
    get("HTTP 200 OK", restTemplate, "http://localhost:8000/");
    get("HTTP 301 Moved Permanently (リダイレクトは自動で処理されるはず)", restTemplate, "http://localhost:8000/?status=301&headers=%7B%22location%22%3A%22http%3A%2F%2Flocalhost%3A8000%2F%22%7D");
    get("HTTP 404 Not Found", restTemplate, "http://localhost:8000/?status=404");
    get("HTTP 500 Internal Server Error", restTemplate, "http://localhost:8000/?status=500");
    get("不明なステータスコード", restTemplate, "http://localhost:8000/?status=599");
    get("URL文字列ではない", restTemplate, "foo");
    get("URL文字列として解析できない", restTemplate, "http://local host:8000/");
    get("URLのスキーム名が不明", restTemplate, "foo://localhost:8000/");
    get("ホスト名からIPアドレスが引けない", restTemplate, "http://localhostlocalhost:8000/");
    get("Webサーバが起動していないポート", restTemplate, "http://localhost:1234/");
    get("信頼できないSSLサーバ証明書 (自己署名証明書, オレオレ証明書)", restTemplate, "https://localhost:8443/");
    get("接続タイムアウト (Connection Timeout) マシンが存在しないIPアドレス", restTemplate, "http://127.0.0.2/");
    get("読み取りタイムアウト (Read Timeout)", restTemplate, "http://localhost:8000/?wait=10");
  }

  /**
   * 指定した URL にアクセスして情報を出力する。
   *
   * @param title        タイトル (どういうパターンかの説明)
   * @param restTemplate HTTP 通信に利用する RestTemplate オブジェクト
   * @param url          アクセスする URL
   */
  private static void get(String title, RestTemplate restTemplate, String url) {
    try {
      System.out.println("************************************************************");
      System.out.println(title);
      System.out.println("URL: " + url);
      URI uri = new URI(url);
      RequestEntity req = RequestEntity.get(uri).build();
      ResponseEntity<String> res = restTemplate.exchange(req, String.class);
      HttpStatus status = res.getStatusCode();
      HttpHeaders headers = res.getHeaders();
      String body = res.getBody();
      System.out.println("Status: " + status);
    } catch (RestClientResponseException e) {
      System.out.println("Class: " + e.getClass().getName());
      int statusCode = e.getRawStatusCode();
      String statusText = e.getStatusText();
      System.out.println("StatusCode: " + statusCode);
      System.out.println("StatusText: " + statusText);
      e.printStackTrace();
    } catch (ResourceAccessException e) {
      System.out.println("Class: " + e.getClass().getName());
      e.printStackTrace();
    } catch (RestClientException e) {
      System.out.println("Class: " + e.getClass().getName());
      e.printStackTrace();
    } catch (URISyntaxException e) {
      System.out.println("Class: " + e.getClass().getName());
      e.printStackTrace();
    } catch (Exception e) {
      System.out.println("Class: " + e.getClass().getName());
      e.printStackTrace();
    }
  }
}

ソースコードのビルド

mvn package コマンドで JAR ファイルを生成する。

$ mvn package

実行結果

サンプルプログラムを実行してそれぞれのパターンでどのような例外が発生しているかを確認する。

$ java -jar target/my-http-client-1.0-SNAPSHOT-jar-with-dependencies.jar 
ClientHttpRequestFactory: org.springframework.http.client.SimpleClientHttpRequestFactory
************************************************************
HTTP 200 OK
URL: http://localhost:8000/
Status: 200 OK
************************************************************
HTTP 301 Moved Permanently (リダイレクトは自動で処理されるはず)
URL: http://localhost:8000/?status=301&headers=%7B%22location%22%3A%22http%3A%2F%2Flocalhost%3A8000%2F%22%7D
Status: 200 OK
************************************************************
HTTP 404 Not Found
URL: http://localhost:8000/?status=404
Class: org.springframework.web.client.HttpClientErrorException$NotFound
StatusCode: 404
StatusText: Not Found
org.springframework.web.client.HttpClientErrorException$NotFound: 404 Not Found
    at org.springframework.web.client.HttpClientErrorException.create(HttpClientErrorException.java:85)
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:122)
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:102)
    at org.springframework.web.client.ResponseErrorHandler.handleError(ResponseErrorHandler.java:63)
    at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:778)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:736)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:35)
************************************************************
HTTP 500 Internal Server Error
URL: http://localhost:8000/?status=500
Class: org.springframework.web.client.HttpServerErrorException$InternalServerError
StatusCode: 500
StatusText: Internal Server Error
org.springframework.web.client.HttpServerErrorException$InternalServerError: 500 Internal Server Error
    at org.springframework.web.client.HttpServerErrorException.create(HttpServerErrorException.java:79)
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:124)
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:102)
    at org.springframework.web.client.ResponseErrorHandler.handleError(ResponseErrorHandler.java:63)
    at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:778)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:736)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:36)
************************************************************
不明なステータスコード
URL: http://localhost:8000/?status=599
Class: org.springframework.web.client.UnknownHttpStatusCodeException
StatusCode: 599
StatusText: null
org.springframework.web.client.UnknownHttpStatusCodeException: Unknown status code [599] null
    at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:100)
    at org.springframework.web.client.ResponseErrorHandler.handleError(ResponseErrorHandler.java:63)
    at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:778)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:736)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:37)
************************************************************
URL文字列ではない
URL: foo
Class: java.lang.IllegalArgumentException
java.lang.IllegalArgumentException: URI is not absolute
    at java.base/java.net.URL.fromURI(URL.java:674)
    at java.base/java.net.URI.toURL(URI.java:1116)
    at org.springframework.http.client.SimpleClientHttpRequestFactory.createRequest(SimpleClientHttpRequestFactory.java:145)
    at org.springframework.http.client.support.HttpAccessor.createRequest(HttpAccessor.java:87)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:731)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:38)
************************************************************
URL文字列として解析できない
URL: http://local host:8000/
Class: java.net.URISyntaxException
java.net.URISyntaxException: Illegal character in authority at index 7: http://local host:8000/
    at java.base/java.net.URI$Parser.fail(URI.java:2915)
    at java.base/java.net.URI$Parser.parseAuthority(URI.java:3249)
    at java.base/java.net.URI$Parser.parseHierarchical(URI.java:3160)
    at java.base/java.net.URI$Parser.parse(URI.java:3116)
    at java.base/java.net.URI.<init>(URI.java:600)
    at com.example.MyHttpClient.get(MyHttpClient.java:60)
    at com.example.MyHttpClient.main(MyHttpClient.java:39)
************************************************************
URLのスキーム名が不明
URL: foo://localhost:8000/
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "foo://localhost:8000/": unknown protocol: foo; nested exception is java.net.MalformedURLException: unknown protocol: foo
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:40)
Caused by: java.net.MalformedURLException: unknown protocol: foo
    at java.base/java.net.URL.<init>(URL.java:634)
    at java.base/java.net.URL.fromURI(URL.java:701)
    at java.base/java.net.URI.toURL(URI.java:1116)
    at org.springframework.http.client.SimpleClientHttpRequestFactory.createRequest(SimpleClientHttpRequestFactory.java:145)
    at org.springframework.http.client.support.HttpAccessor.createRequest(HttpAccessor.java:87)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:731)
    ... 3 more
************************************************************
ホスト名からIPアドレスが引けない
URL: http://localhostlocalhost:8000/
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhostlocalhost:8000/": localhostlocalhost; nested exception is java.net.UnknownHostException: localhostlocalhost
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:41)
Caused by: java.net.UnknownHostException: localhostlocalhost
    at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:220)
    at java.base/java.net.Socket.connect(Socket.java:591)
    at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:177)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
    at java.base/sun.net.www.http.HttpClient.<init>(HttpClient.java:242)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1242)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1181)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1075)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:1009)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:735)
    ... 3 more
************************************************************
Webサーバが起動していないポート
URL: http://localhost:1234/
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhost:1234/": Connection refused (Connection refused); nested exception is java.net.ConnectException: Connection refused (Connection refused)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:42)
Caused by: java.net.ConnectException: Connection refused (Connection refused)
    at java.base/java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
    at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
    at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
    at java.base/java.net.Socket.connect(Socket.java:591)
    at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:177)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
    at java.base/sun.net.www.http.HttpClient.<init>(HttpClient.java:242)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1242)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1181)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1075)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:1009)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:735)
    ... 3 more
************************************************************
信頼できないSSLサーバ証明書 (自己署名証明書, オレオレ証明書)
URL: https://localhost:8443/
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "https://localhost:8443/": PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target; nested exception is javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:43)
Caused by: javax.net.ssl.SSLHandshakeException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at java.base/sun.security.ssl.Alert.createSSLException(Alert.java:128)
    at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:321)
    at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:264)
    at java.base/sun.security.ssl.TransportContext.fatal(TransportContext.java:259)
    at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.checkServerCerts(CertificateMessage.java:642)
    at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.onCertificate(CertificateMessage.java:461)
    at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.consume(CertificateMessage.java:361)
    at java.base/sun.security.ssl.SSLHandshake.consume(SSLHandshake.java:392)
    at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:444)
    at java.base/sun.security.ssl.HandshakeContext.dispatch(HandshakeContext.java:421)
    at java.base/sun.security.ssl.TransportContext.dispatch(TransportContext.java:178)
    at java.base/sun.security.ssl.SSLTransport.decode(SSLTransport.java:164)
    at java.base/sun.security.ssl.SSLSocketImpl.decode(SSLSocketImpl.java:1152)
    at java.base/sun.security.ssl.SSLSocketImpl.readHandshakeRecord(SSLSocketImpl.java:1063)
    at java.base/sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:402)
    at java.base/sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:567)
    at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:185)
    at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImpl.java:163)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:735)
    ... 3 more
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:385)
    at java.base/sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:290)
    at java.base/sun.security.validator.Validator.validate(Validator.java:264)
    at java.base/sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:321)
    at java.base/sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:221)
    at java.base/sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:129)
    at java.base/sun.security.ssl.CertificateMessage$T12CertificateConsumer.checkServerCerts(CertificateMessage.java:626)
    ... 20 more
Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at java.base/sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
    at java.base/sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
    at java.base/java.security.cert.CertPathBuilder.build(CertPathBuilder.java:297)
    at java.base/sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:380)
    ... 26 more
************************************************************
接続タイムアウト (Connection Timeout) マシンが存在しないIPアドレス
URL: http://127.0.0.2/
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://127.0.0.2/": connect timed out; nested exception is java.net.SocketTimeoutException: connect timed out
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:44)
Caused by: java.net.SocketTimeoutException: connect timed out
    at java.base/java.net.PlainSocketImpl.socketConnect(Native Method)
    at java.base/java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:399)
    at java.base/java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:242)
    at java.base/java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:224)
    at java.base/java.net.Socket.connect(Socket.java:591)
    at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:177)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
    at java.base/sun.net.www.http.HttpClient.<init>(HttpClient.java:242)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
    at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1242)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1181)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1075)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:1009)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:735)
    ... 3 more
************************************************************
読み取りタイムアウト (Read Timeout)
URL: http://localhost:8000/?wait=10
Class: org.springframework.web.client.ResourceAccessException
org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhost:8000/": Read timed out; nested exception is java.net.SocketTimeoutException: Read timed out
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:744)
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:637)
    at com.example.MyHttpClient.get(MyHttpClient.java:62)
    at com.example.MyHttpClient.main(MyHttpClient.java:45)
Caused by: java.net.SocketTimeoutException: Read timed out
    at java.base/java.net.SocketInputStream.socketRead0(Native Method)
    at java.base/java.net.SocketInputStream.socketRead(SocketInputStream.java:115)
    at java.base/java.net.SocketInputStream.read(SocketInputStream.java:168)
    at java.base/java.net.SocketInputStream.read(SocketInputStream.java:140)
    at java.base/java.io.BufferedInputStream.fill(BufferedInputStream.java:252)
    at java.base/java.io.BufferedInputStream.read1(BufferedInputStream.java:292)
    at java.base/java.io.BufferedInputStream.read(BufferedInputStream.java:351)
    at java.base/sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:746)
    at java.base/sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:689)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1604)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1509)
    at java.base/java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:527)
    at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:82)
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:735)
    ... 3 more

参考資料

Register as a new user and use Qiita more conveniently

  1. You get articles that match your needs
  2. You can efficiently read back useful information
  3. You can use dark theme
What you can do with signing up
19