maven编译时错误：无效的目标发行版

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>Tools<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>Tools<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>1.0<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">dependencies</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">dependency</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>org.apache.httpcomponents<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>httpclient<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>4.1<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">dependency</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">dependency</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>org.apache.httpcomponents<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">groupId</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>httpmime<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>4.1<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">version</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">dependency</span><span style="color: #0000ff;">&gt;</span>

<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">dependencies</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">build</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">plugins</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">plugin</span><span style="color: #0000ff;">&gt;</span>
            <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>maven-assembly-plugin<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">artifactId</span><span style="color: #0000ff;">&gt;</span>
            <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">configuration</span><span style="color: #0000ff;">&gt;</span>
                <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">descriptorRefs</span><span style="color: #0000ff;">&gt;</span>
                    <span style="color: #0000ff;">&lt;</span><span style="color: #800000;">descriptorRef</span><span style="color: #0000ff;">&gt;</span>jar-with-dependencies<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">descriptorRef</span><span style="color: #0000ff;">&gt;</span>
                <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">descriptorRefs</span><span style="color: #0000ff;">&gt;</span>
            <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">configuration</span><span style="color: #0000ff;">&gt;</span>
        <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">plugin</span><span style="color: #0000ff;">&gt;</span>
    <span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">plugins</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">build</span><span style="color: #0000ff;">&gt;</span>
<span style="color: #0000ff;">&lt;</span><span style="color: #800000;">packaging</span><span style="color: #0000ff;">&gt;</span>jar<span style="color: #0000ff;">&lt;/</span><span style="color: #800000;">packaging</span><span style="color: #0000ff;">&gt;</span>

</project>