OracleJdk与openJdk差异引起的NoClassDefFoundError/ClassNotFoundException

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我是靠谱客的博主潇洒白开水，最近开发中收集的这篇文章主要介绍OracleJdk与openJdk差异引起的NoClassDefFoundError/ClassNotFoundException，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

本地开发好之后，调试运行都没有问题，部署在服务器上运行直接报了以下Error：

Exception in thread "warehouseStart-9001" java.lang.NoClassDefFoundError: javafx/util/Pair
at com.kc.evo.wcs.adapter.impl.BasicMapServiceImpl.selectByWarehouse(BasicMapServiceImpl.java:163)
at com.kc.evo.wcs.application.init.WarehouseStart.buildMap(WarehouseStart.java:301)
at com.kc.evo.wcs.application.init.WarehouseStart.run(WarehouseStart.java:103)
Caused by: java.lang.ClassNotFoundException: javafx.util.Pair
at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:93)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

　　一开始还很不可思议，以为服务器没装jdk，java -version后发现也装了jdk1.8。后来在排查过程中发现因为在Windows环境下开发使用的是Oracle官网下载的OracleJdk，而服务器上使用的是OpenJdk。两者还是有一点点差距的，OpenJdk中没有

javafx这个包导致了上面异常的出现。解决方法，在项目中自定义Pair，将项目中使用到javafx.util.Pair的地方改为自定义Pair。

javafx.util.Pair很容易理解，贴一下源码。

public class Pair<K,V> implements Serializable{

    /**
     * Key of this <code>Pair</code>.
     */
    private K key;

    /**
     * Gets the key for this pair.
     * @return key for this pair
     */
    public K getKey() { return key; }

    /**
     * Value of this this <code>Pair</code>.
     */
    private V value;

    /**
     * Gets the value for this pair.
     * @return value for this pair
     */
    public V getValue() { return value; }

    /**
     * Creates a new pair
     * @param key The key for this pair
     * @param value The value to use for this pair
     */
    public Pair(@NamedArg("key") K key, @NamedArg("value") V value) {
        this.key = key;
        this.value = value;
    }

    /**
     * <p><code>String</code> representation of this
     * <code>Pair</code>.</p>
     *
     * <p>The default name/value delimiter '=' is always used.</p>
     *
     *  @return <code>String</code> representation of this <code>Pair</code>
     */
    @Override
    public String toString() {
        return key + "=" + value;
    }

    /**
     * <p>Generate a hash code for this <code>Pair</code>.</p>
     *
     * <p>The hash code is calculated using both the name and
     * the value of the <code>Pair</code>.</p>
     *
     * @return hash code for this <code>Pair</code>
     */
    @Override
    public int hashCode() {
        // name's hashCode is multiplied by an arbitrary prime number (13)
        // in order to make sure there is a difference in the hashCode between
        // these two parameters:
        //  name: a  value: aa
        //  name: aa value: a
        return key.hashCode() * 13 + (value == null ? 0 : value.hashCode());
    }

     /**
      * <p>Test this <code>Pair</code> for equality with another
      * <code>Object</code>.</p>
      *
      * <p>If the <code>Object</code> to be tested is not a
      * <code>Pair</code> or is <code>null</code>, then this method
      * returns <code>false</code>.</p>
      *
      * <p>Two <code>Pair</code>s are considered equal if and only if
      * both the names and values are equal.</p>
      *
      * @param o the <code>Object</code> to test for
      * equality with this <code>Pair</code>
      * @return <code>true</code> if the given <code>Object</code> is
      * equal to this <code>Pair</code> else <code>false</code>
      */
     @Override
     public boolean equals(Object o) {
         if (this == o) return true;
         if (o instanceof Pair) {
             Pair pair = (Pair) o;
             if (key != null ? !key.equals(pair.key) : pair.key != null) return false;
             if (value != null ? !value.equals(pair.value) : pair.value != null) return false;
             return true;
         }
         return false;
     }
 }