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环境： ubuntu 16.04, Eclipse Java EE IDE for Web Developers.(Version: Neon.2 Release (4.6.2))

架包 objectdetection_lib.jar 中 ObjectDetectionImplement.class 中有调用 System.loadLibrary

static{
        System.loadLibrary("objectdetection");
}

1. 运行时出现以下错误：

/usr/java/packages/lib/amd64:/usr/lib64:/lib64:/lib:/usr/lib
sun.arch.data.model = 64
Exception in thread "main" java.lang.UnsatisfiedLinkError: no objectdetection in java.library.path
	at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1867)
	at java.lang.Runtime.loadLibrary0(Runtime.java:870)
	at java.lang.System.loadLibrary(System.java:1122)
	at objectdetection.ObjectDetectionImplement.<clinit>(ObjectDetectionImplement.java:35)
	at objectdetection_demo.ObjectDetection.main(ObjectDetection.java:23)

此错误需要 将 libobjectdetection.so 所在路径 添加至 java.library.path 环境变量中（即 LD_LIBRARY_PATH）;

具体步骤如下:

Run –> Debug Configures –> Enviroment –> new, 在弹出的 New Environment Variable,

Name: LD_LIBRARY_PATH;

Value:  /home/robert/Documents/code/objectdetection/build/linux；

2. 出现 System.loadLibrary 库依赖的库无法找到，报错提示的是依赖库的符号找不到,此时需要指定依赖的库路径及库名称;

Exception in thread "main" java.lang.UnsatisfiedLinkError: /home/robert/Documents/code/objectdetection/build/linux/libobjectdetection.so: /home/robert/Documents/code/objectdetection/build/linux/libobjectdetection.so: undefined symbol: WebPMemoryWrite
	at java.lang.ClassLoader$NativeLibrary.load(Native Method)
	at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1941)
	at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1857)
	at java.lang.Runtime.loadLibrary0(Runtime.java:870)
	at java.lang.System.loadLibrary(System.java:1122)
	at objectdetection.ObjectDetectionImplement.<clinit>(ObjectDetectionImplement.java:35)
	at objectdetection_demo.ObjectDetection.main(ObjectDetection.java:23)

此错误需要 将  libobjectdetection.so 依赖的 所在路径及库名称 添加至 LD_PRELOAD 环境变量中;

具体步骤如下:

Run –> Debug Configures –> Enviroment –> new, 在弹出的 New Environment Variable, 各依赖库间以空格分隔；

Name: LD_PRELOAD;

Value:  /home/robert/Documents/code/objectdetection/lib/linux_64/libwebp/libwebp.so /home/robert/Documents/code/objectdetection/lib/linux_64/libwebp/libwebpdemux.so /home/robert/Documents/code/objectdetection/lib/linux_64/libwebp/libwebpmux.so  /usr/local/lib/libopencv_imgcodecs.so /home/robert/Documents/code/objectdetection/lib/linux_64/libfcn.so /home/robert/ubuntu_env/libopenblas_hh/libopenblas.so

截图如下: