This is one of this issue...

In JarSignerResources.java, there are the following resources.

{"certificate valid from ", "certificate valid from "},
{" to ", " to "},
{"certificate expired on ", "certificate expired on "},
{"certificate is not valid until ", "certificate is not valid until "},
{"certificate will expire on ", "certificate will expire on "},

In JarSigner.java, it's using the resources as below.

        if (notAfter.getTime() < now + SIX_MONTHS) {
            hasExpiringCert = true;
            certStr.append(rb.getString("certificate will expire on "))
            .append(notAfter);
        } else {
            certStr.append(rb.getString("certificate valid from "))
            .append(x509Cert.getNotBefore())
            .append(rb.getString(" to "))
            .append(notAfter);
        }
        } catch (CertificateExpiredException cee) {
        hasExpiredCert = true;
        certStr.append(rb.getString("certificate expired on "))
            .append(notAfter);
        } catch (CertificateNotYetValidException cnyve) {
        notYetValidCert = true;
        certStr.append(rb.getString("certificate is not valid until "))
            .append(x509Cert.getNotBefore());
        }

Actual message texts should be:

  "certificate will expire on <date>"
  "certificate valid from <date> to <date>"
  "certificate expired on <date>"
  "certificate is not valid until <date>"

Translators look at only the text in the resource files and
attempt to translate the message text, so an actual translated
message will become the strange thing to which the string of
parameter(s) like "<date>" is attached at the end of the message
unnaturally.

The message which has parameter(s) as a part of the message
should include variable(s) '{n}' in the message itself like below.

{"certificate valid from ", "certificate valid from {0} to {1}"},
{"certificate expired on ", "certificate expired on {0}"},
{"certificate is not valid until ", "certificate is not valid until {0}"},
{"certificate will expire on ", "certificate will expire on {0}"},

In the result, translators will be able to translate it naturally.