[平台默认字符集]java.lang.System.getProperties()
方法一：
java.nio.charset.Charset.defaultCharset();
package com.wxg.util;import java.security.Provider;import java.security.Security;import java.util.Iterator;import java.util.Properties;import java.util.Set;public class Test {public void testOne(){Provider[] providers = Security.getProviders();for(int i=0; i<providers.length; i++){Provider p = providers[i];System.out.println("getName : " + p.getName() + ", getInfo : " + p.getInfo());}}public void testTwo(){Properties pros = System.getProperties();/*Enumeration enumeration = pros.propertyNames();while(enumeration.hasMoreElements()){System.out.println(enumeration.nextElement());}*/Set<String> sets = pros.stringPropertyNames();Iterator<String> it = sets.iterator();int num = 1;while(it.hasNext()){System.out.println(num + " : " + it.next());num++;}}public void testThree(){Properties pro = System.getProperties();String[] pNames = new String[]{"file.encoding.pkg","user.country","sun.jnu.encoding","file.encoding","user.language","sun.io.unicode.encoding"};for(int i=0; i<pNames.length; i++){System.out.println((i+1) + " : " + pNames[i] + " = " + pro.getProperty(pNames[i]));}}public static void main(String[] args) {Test t = new Test();t.testOne();t.testTwo();t.testThree();}}output:getName : SUN, getInfo : SUN (DSA key/parameter generation; DSA signing; SHA-1, MD5 digests; SecureRandom; X.509 certificates; JKS keystore; PKIX CertPathValidator; PKIX CertPathBuilder; LDAP, Collection CertStores, JavaPolicy Policy; JavaLoginConfig Configuration)getName : SunRsaSign, getInfo : Sun RSA signature providergetName : SunJSSE, getInfo : Sun JSSE provider(PKCS12, SunX509 key/trust factories, SSLv3, TLSv1)getName : SunJCE, getInfo : SunJCE Provider (implements RSA, DES, Triple DES, AES, Blowfish, ARCFOUR, RC2, PBE, Diffie-Hellman, HMAC)getName : SunJGSS, getInfo : Sun (Kerberos v5, SPNEGO)getName : SunSASL, getInfo : Sun SASL provider(implements client mechanisms for: DIGEST-MD5, GSSAPI, EXTERNAL, PLAIN, CRAM-MD5; server mechanisms for: DIGEST-MD5, GSSAPI, CRAM-MD5)getName : XMLDSig, getInfo : XMLDSig (DOM XMLSignatureFactory; DOM KeyInfoFactory)getName : SunPCSC, getInfo : Sun PC/SC providergetName : SunMSCAPI, getInfo : Sun's Microsoft Crypto API provider1 : java.runtime.name2 : sun.boot.library.path3 : java.vm.version4 : java.vm.vendor5 : java.vendor.url6 : path.separator7 : java.vm.name8 : file.encoding.pkg9 : user.country10 : sun.java.launcher11 : sun.os.patch.level12 : java.vm.specification.name13 : user.dir14 : java.runtime.version15 : java.awt.graphicsenv16 : java.endorsed.dirs17 : os.arch18 : java.io.tmpdir19 : line.separator20 : java.vm.specification.vendor21 : user.variant22 : os.name23 : sun.jnu.encoding24 : java.library.path25 : java.specification.name26 : java.class.version27 : sun.management.compiler28 : os.version29 : user.home30 : user.timezone31 : java.awt.printerjob32 : file.encoding33 : java.specification.version34 : user.name35 : java.class.path36 : java.vm.specification.version37 : sun.arch.data.model38 : java.home39 : sun.java.command40 : java.specification.vendor41 : user.language42 : awt.toolkit43 : java.vm.info44 : java.version45 : java.ext.dirs46 : sun.boot.class.path47 : java.vendor48 : file.separator49 : java.vendor.url.bug50 : sun.cpu.endian51 : sun.io.unicode.encoding52 : sun.desktop53 : sun.cpu.isalist1 : file.encoding.pkg = sun.io2 : user.country = CN3 : sun.jnu.encoding = GBK4 : file.encoding = GBK5 : user.language = zh6 : sun.io.unicode.encoding = UnicodeLittle