我正在尝试从URL加载JSON，必要时在另一个答案中 simplest way to read json from a URL in java
但是，我正在尝试使用Roland给出的答案，而这本身并不起作用。 JSON库正在正常工作和导入，但在尝试打开URL流时出现以下错误：
Exception in thread "main" java.net.SocketException: java.security.NoSuchAlgorithmException: Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)
at javax.net.ssl.DefaultSSLSocketFactory.throwException(SSLSocketFactory.java:248)
at javax.net.ssl.DefaultSSLSocketFactory.createSocket(SSLSocketFactory.java:255)
at sun.net.www.protocol.https.HttpsClient.createSocket(HttpsClient.java:405)
at sun.net.NetworkClient.doConnect(NetworkClient.java:162)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:432)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:527)
at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:264)
at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:367)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:191)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1105)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:999)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:177)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1513)
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1441)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:254)
at java.net.URL.openStream(URL.java:1038)
at JsonReader.readJsonFromUrl(JsonReader.java:24)
at JsonReader.main(JsonReader.java:36)
Caused by: java.security.NoSuchAlgorithmException: Error constructing implementation (algorithm: Default, provider: SunJSSE, class: sun.security.ssl.SSLContextImpl$DefaultSSLContext)
at java.security.Provider$Service.newInstance(Provider.java:1617)
at sun.security.jca.GetInstance.getInstance(GetInstance.java:236)
at sun.security.jca.GetInstance.getInstance(GetInstance.java:164)
at javax.net.ssl.SSLContext.getInstance(SSLContext.java:156)
at javax.net.ssl.SSLContext.getDefault(SSLContext.java:96)
at javax.net.ssl.SSLSocketFactory.getDefault(SSLSocketFactory.java:122)
at javax.net.ssl.HttpsURLConnection.getDefaultSSLSocketFactory(HttpsURLConnection.java:332)
at javax.net.ssl.HttpsURLConnection.<init>(HttpsURLConnection.java:289)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.<init>(HttpsURLConnectionImpl.java:85)
at sun.net.www.protocol.https.Handler.openConnection(Handler.java:62)
at sun.net.www.protocol.https.Handler.openConnection(Handler.java:57)
at java.net.URL.openConnection(URL.java:972)
... 3 more
Caused by: java.io.IOException: Invalid keystore format
at sun.security.provider.JavaKeyStore.engineLoad(JavaKeyStore.java:658)
at sun.security.provider.JavaKeyStore$JKS.engineLoad(JavaKeyStore.java:56)
at sun.security.provider.KeyStoreDelegator.engineLoad(KeyStoreDelegator.java:225)
at sun.security.provider.JavaKeyStore$DualFormatJKS.engineLoad(JavaKeyStore.java:70)
at java.security.KeyStore.load(KeyStore.java:1445)
at sun.security.ssl.TrustManagerFactoryImpl.getCacertsKeyStore(TrustManagerFactoryImpl.java:226)
at sun.security.ssl.SSLContextImpl$DefaultSSLContext.getDefaultTrustManager(SSLContextImpl.java:767)
at sun.security.ssl.SSLContextImpl$DefaultSSLContext.<init>(SSLContextImpl.java:733)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at java.security.Provider$Service.newInstance(Provider.java:1595)
... 14 more
如果有人知道导致此问题的原因，我们将非常感谢任何帮助！
编辑 - 从链接中添加原始代码...
package so4308554;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URL;
import java.nio.charset.Charset;
import org.json.JSONException;
import org.json.JSONObject;
public class JsonReader {
private static String readAll(Reader rd) throws IOException {
StringBuilder sb = new StringBuilder();
int cp;
while ((cp = rd.read()) != -1) {
sb.append((char) cp);
}
return sb.toString();
}
public static JSONObject readJsonFromUrl(String url) throws IOException, JSONException {
InputStream is = new URL(url).openStream();
try {
BufferedReader rd = new BufferedReader(new InputStreamReader(is, Charset.forName("UTF-8")));
String jsonText = readAll(rd);
JSONObject json = new JSONObject(jsonText);
return json;
} finally {
is.close();
}
}
public static void main(String[] args) throws IOException, JSONException {
JSONObject json = readJsonFromUrl("https://graph.facebook.com/19292868552");
System.out.println(json.toString());
System.out.println(json.get("id"));
}
}