JDK 1.5 and higher

当前jdk版本的spring不支持注解，所以要换jdk，或者加一个配置文件。
我一般是在src文件夹加org.springframework.core包,并添加一个JdkVersion.java文件。
使注解能够识别jdk8。

public abstract class JdkVersion {
    /*** Constant identifying the 1.3.x JVM (JDK 1.3).*/public static final int JAVA_13 = 0;/*** Constant identifying the 1.4.x JVM (J2SE 1.4).*/public static final int JAVA_14 = 1;/*** Constant identifying the 1.5 JVM (Java 5).*/public static final int JAVA_15 = 2;/*** Constant identifying the 1.6 JVM (Java 6).*/public static final int JAVA_16 = 3;/*** Constant identifying the 1.7 JVM (Java 7).*/public static final int JAVA_17 = 4;/*** Constant identifying the 1.8 JVM (Java 8).*/public static final int JAVA_18 = 5;private static final String javaVersion;private static final int majorJavaVersion;static {
    javaVersion = System.getProperty("java.version");// version String should look like "1.4.2_10"if (javaVersion.contains("1.8.")) {
    majorJavaVersion = JAVA_18;}else if (javaVersion.contains("1.7.")) {
    majorJavaVersion = JAVA_17;}else if (javaVersion.contains("1.6.")) {
    majorJavaVersion = JAVA_16;}else {
    // else leave 1.5 as default (it's either 1.5 or unknown)majorJavaVersion = JAVA_15;}}/*** Return the full Java version string, as returned by* <code>System.getProperty("java.version")</code>.* @return the full Java version string* @see System#getProperty(String)*/public static String getJavaVersion() {
    return javaVersion;}/*** Get the major version code. This means we can do things like* <code>if (getMajorJavaVersion() < JAVA_14)</code>.* @return a code comparable to the JAVA_XX codes in this class* @see #JAVA_13* @see #JAVA_14* @see #JAVA_15* @see #JAVA_16* @see #JAVA_17*/public static int getMajorJavaVersion() {
    return majorJavaVersion;}/*** Convenience method to determine if the current JVM is at least Java 1.4.* @return <code>true</code> if the current JVM is at least Java 1.4* @deprecated as of Spring 3.0 which requires Java 1.5+* @see #getMajorJavaVersion()* @see #JAVA_14* @see #JAVA_15* @see #JAVA_16* @see #JAVA_17*/@Deprecatedpublic static boolean isAtLeastJava14() {
    return true;}/*** Convenience method to determine if the current JVM is at least* Java 1.5 (Java 5).* @return <code>true</code> if the current JVM is at least Java 1.5* @deprecated as of Spring 3.0 which requires Java 1.5+* @see #getMajorJavaVersion()* @see #JAVA_15* @see #JAVA_16* @see #JAVA_17*/@Deprecatedpublic static boolean isAtLeastJava15() {
    return true;}/*** Convenience method to determine if the current JVM is at least* Java 1.6 (Java 6).* @return <code>true</code> if the current JVM is at least Java 1.6* @deprecated as of Spring 3.0, in favor of reflective checks for* the specific Java 1.6 classes of interest* @see #getMajorJavaVersion()* @see #JAVA_16* @see #JAVA_17*/@Deprecatedpublic static boolean isAtLeastJava16() {
    return (majorJavaVersion >= JAVA_16);}}