在eclipse中将外部jar添加到android项目中

Question

我正在使用google-api-java-client在eclipse中构建一个简单的Android项目.我正在尝试按照本教程启动并运行它.我在SO中搜索了如何将JAR添加到Eclipse中的Android项目的答案.他们中的大多数建议将JAR添加到lib/Android项目内的文件夹中,然后将这些JAR添加到项目的构建路径中.我做了这两件事.该项目编译良好(无论如何,Eclipse不会抱怨任何错误).但是当我在我的模拟器中运行Android应用程序时,ClassDefNotFoundError每当我尝试实例化google-api-java-clientJAR中的任何类时,我都会得到它.例如

new com.google.api.client.http.apache.ApacheHttpTransport();

提高ClassDefNotFoundError.

以下是导致错误的代码:

package com.mycom.android;

import android.view.View;
import android.view.View.OnClickListener;
import android.widget.EditText;

public class SearchRunner implements OnClickListener {

    private static final String API_KEY = "AIzaSyA1Mg3xWXfoov4HdPUzYY2NwTxuvCev1-E";
    private static final String PLACES_SEARCH_URL = "";

    @Override
    public void onClick(View v) {
        EditText editText = (EditText) v;
        String searchText = editText.getText().toString();
        runSearch(searchText);
    }

    protected void runSearch(String searchText) {
        new com.google.api.client.http.apache.ApacheHttpTransport();
    }

}

以下是Eclipse LogCat的更完整输出:

12-21 15:42:11.402: E/dalvikvm(3412): Could not find class 'com.google.api.client.http.apache.ApacheHttpTransport', referenced from method com.mycom.android.SearchRunner.runSearch
12-21 15:42:11.402: W/dalvikvm(3412): VFY: unable to resolve new-instance 70 (Lcom/google/api/client/http/apache/ApacheHttpTransport;) in Lcom/mycom/android/SearchRunner;
12-21 15:42:11.402: D/dalvikvm(3412): VFY: replacing opcode 0x22 at 0x0000
12-21 15:42:11.402: D/dalvikvm(3412): DexOpt: unable to opt direct call 0x00ca at 0x02 in Lcom/mycom/android/SearchRunner;.runSearch
12-21 15:42:11.682: I/MapActivity(3412): Handling network change notification:CONNECTED
12-21 15:42:11.682: E/MapActivity(3412): Couldn't get connection factory client
12-21 15:42:11.791: D/gralloc_goldfish(3412): Emulator without GPU emulation detected.
12-21 15:42:12.532: D/dalvikvm(3412): GC_CONCURRENT freed 102K, 3% free 10520K/10823K, paused 5ms+7ms
12-21 15:42:18.422: D/AndroidRuntime(3412): Shutting down VM
12-21 15:42:18.422: W/dalvikvm(3412): threadid=1: thread exiting with uncaught exception (group=0x409951f8)
12-21 15:42:18.482: E/AndroidRuntime(3412): FATAL EXCEPTION: main
12-21 15:42:18.482: E/AndroidRuntime(3412): java.lang.NoClassDefFoundError: com.google.api.client.http.apache.ApacheHttpTransport
12-21 15:42:18.482: E/AndroidRuntime(3412):     at com.mycom.android.SearchRunner.runSearch(SearchRunner.java:20)

Answer 1

我按照这些说明逐步解决了这个问题.当我最初开始设置项目时:

1. 我将google-api-java-client项目中的JAR文件导入到项目的lib/文件夹中
2. 我右键单击lib/google-api-client...并选择了Build Path> Add To Build Path

此时,在Eclipse中,我的项目的"Referenced Libraries"部分下出现了一堆库:

jsr305-1.3.9.jar
gson-1.7.1.jar
guava-r09.jar
junit-4.8.2.jar
httpclient-4.0.3.jar
httpcore-4.0.1.jar
commons-logging-1.1.1.jar
commons-codec-1.3.jar
jackson-core-asl-1.9.1.jar
xpp3-1.1.4c.jar
protobuf-java-2.2.0.jar
google-http-client-1.6.0-beta.jar
google-oauth-client-1.6.0-beta.jar
google-api-client-1.6.0-beta.jar

但是,当我进入Project> Properties> Java Build Path> Libraries时,我看到只google-api-client...列出了它.当我试图运行该项目时,我得到了原始文章中提到的NoClassDefFounErrorfor ApacheHttpTransport.这是因为该类在google-http-client!中定义.通过手动添加google-http-client到构建路径,问题得以解决.

获得的经验教训:仅仅因为在Eclipse项目的"引用库"下列出了JAR并不意味着这些JAR包含在项目的构建路径中.