Java Key Public getPublicKeyFromString(String certificateString)

Description

Get RSA public key from X.509 certificate string (full crt file content, including header and footer)

License

Apache License

Parameter

Parameter	Description
certificateString	certificate string

Exception

Parameter	Description
CertificateException	an exception
UnsupportedEncodingException	an exception

Return

RSA public key

Declaration

public static RSAPublicKey getPublicKeyFromString(String certificateString)
        throws CertificateException, UnsupportedEncodingException 

Method Source Code

//package com.java2s;
/*/*from  ww  w.j a v  a  2 s .c o  m*/
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.ByteArrayInputStream;

import java.io.UnsupportedEncodingException;
import java.security.cert.CertificateException;
import java.security.cert.CertificateFactory;
import java.security.cert.X509Certificate;
import java.security.interfaces.RSAPublicKey;

public class Main {
    /**
     * Get RSA public key from X.509 certificate string (full crt file content, including header and footer)
     * @param certificateString certificate string
     * @return RSA public key
     * @throws CertificateException
     * @throws UnsupportedEncodingException
     */
    public static RSAPublicKey getPublicKeyFromString(String certificateString)
            throws CertificateException, UnsupportedEncodingException {

        CertificateFactory fact = CertificateFactory.getInstance("X.509");
        ByteArrayInputStream is = new ByteArrayInputStream(certificateString.getBytes("UTF8"));

        X509Certificate cer = (X509Certificate) fact.generateCertificate(is);
        return (RSAPublicKey) cer.getPublicKey();
    }
}

Related

1. getPublicKey(String publicKeyFile)
2. getPublicKey(String publicKeyFilepath, String algorithm)
3. getPublicKeyFromBytes(final String algorithm, final byte[] publicKeyBytes)
4. getPublicKeyFromFile(File cert, String alias, String password)
5. getPublicKeyFromPEMFile(String fileName, String jceProvider)
6. getPublicKeyModulus(RSAPublicKey publicKey)
7. getPublicKeySpec(KeyPair kp)
8. getPublicPutMethodForResultClass(final Class resultClass)