…… are only available on JDK 1.5 and higher 错误（spring 的jdk版本检测在jdk 8下的修订）

java.lang.IllegalStateException: Context namespace element 'component-scan' and its parser class [org.springframework.context.annotation.ComponentScanBeanDefinitionParser] are only available on JDK 1.5 and higher

 

项目中用的是spring低版本（2.5.6），今天用jre 8测试了一下，发现错误： 
Unexpected exception parsing XML document from class path resource [applicationContext-dao.xml]; nested exception isJava.lang.IllegalStateException: Context namespace element ‘annotation-config’ and its parser class [org.springframework.context.annotation.AnnotationConfigBeanDefinitionParser] are only available on JDK 1.5 and higher

看源码是org.springframework.context.annotation.AnnotationConfigBeanDefinitionParser自动检测，jdk版本检测时须要jre1.5以上版本，可是JdkVersion只检查到了1.7，jre1.8 时不匹配任何jdk，按以下方法处理，能够解决问题。

一、在项目中建立一个package为org.springframework.core 
二、在该package下面新建JdkVersion.java，内容以下：

package org.springframework.core;

public abstract class JdkVersion {
    public static final int JAVA_13 = 0;
    public static final int JAVA_14 = 1;
    public static final int JAVA_15 = 2;
    public static final int JAVA_16 = 3;
    public static final int JAVA_17 = 4;
    //for jre 1.8
    public static final int JAVA_18 = 5;
    private static final String javaVersion = System
            .getProperty("java.version");
    private static final int majorJavaVersion;
    public static String getJavaVersion() {
        return javaVersion;
    }
    public static int getMajorJavaVersion() {
        return majorJavaVersion;
    }
    public static boolean isAtLeastJava14() {
        return true;
    }
    public static boolean isAtLeastJava15() {
        return getMajorJavaVersion() >= 2;
    }
    public static boolean isAtLeastJava16() {
        return getMajorJavaVersion() >= 3;
    }
    static {
        //for jre 1.8
        if (javaVersion.indexOf("1.8.") != -1) {
            majorJavaVersion = 5;
        }else if (javaVersion.indexOf("1.7.") != -1) {
            majorJavaVersion = 4;
        } else if (javaVersion.indexOf("1.6.") != -1) {
            majorJavaVersion = 3;
        } else if (javaVersion.indexOf("1.5.") != -1) {
            majorJavaVersion = 2;
        } else {
            majorJavaVersion = 1;
        }
    }
}

三、到项目的WEB-INF/classes 下面找到对应的package中的JdkVersion.class文件 
四、将项目中的spring-core-2.5.6.jar拷贝出来打开，而后将JdkVersion.class替换jar包中的该文件。 
五、将修改后的spring-core-2.5.6.jar再覆盖到项目中。

这样，再启动项目就不会出现错误了。