java.lang.UnsatisfiedLinkError：找不到本機方法：

Question

調用在.SO文件中編譯的本機方法時，我總是收到此錯誤。 我不知道為什么會發生這種情況，因為一切似乎都已正確設置，任何幫助將不勝感激

錯誤：

java.lang.UnsatisfiedLinkError: Native method not found: de.jurihock.voicesmith.dsp.Math.abs:(FF)F
at de.jurihock.voicesmith.dsp.Math.abs(Native Method)

cpp文件： pastebin.com/aBHNz642

Math.java

 package de.jurihock.voicesmith.dsp;

public final class Math
{
     static
        {
        System.loadLibrary("Voicesmith");
        }

public static final float   PI  = (float) java.lang.Math.PI;

public static int round(float value)
{
    return java.lang.Math.round(value);
}

public static native float pow(float base, float exponent);

public static native float log10(float value);

public static native float min(float a, float b);

public static native float max(float a, float b);

public static native float floor(float value);

public static native float ceil(float value);

public static native float sin(float angle);

public static native float cos(float angle);

public static native float sqrt(float value);

public static native float atan2(float y, float x);

public  native float abs(float real, float imag);

public static native float arg(float real, float imag);

public static native float real(float abs, float arg);

public static native float imag(float abs, float arg);

public static native float random(float min, float max);

public static native float princarg(float phase);

public static native short mean(short[] buffer, int offset, int length);

public static native float rms(short[] buffer, int offset, int length);

public static native float rms(short[] buffer, int offset, int length, short mean);

public static native float rms2dbfs(float value, float min, float max);

}

android.mk

    LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

# Name of the library without prefix "lib" and file extension
LOCAL_MODULE := Voicesmith

# Optimization flags (see KissFFT makefile)
LOCAL_ARM_MODE := arm
LOCAL_CFLAGS := -Wall -O3 -ffast-math -funroll-loops -fomit-frame-pointer

# LogCat support
# LOCAL_LDLIBS := -llog

# Debugging flag
# LOCAL_CFLAGS += -g

# Include all .c/.cpp files to build
LOCAL_SRC_FILES := $(shell cd $(LOCAL_PATH); \
    find . -type f -name '*.c'; \
    find . -type f -name '*.cpp')

include $(BUILD_SHARED_LIBRARY)

Answer 1

您的本機方法abs在其聲明中缺少static 。 您的版本應該已經捕獲了錯誤，Android Studio確實如此。

嘗試將其更改為

public static native float abs(float real, float imag);

其他一些建議：

• 名稱Math.h可能與本機端的標准math.h沖突（如果在Windows上嘗試，甚至都不會編譯，因為Windows文件系統不區分大小寫...我必須將Math.h更改為Math2.h）。

• 即使在Java方面， java.lang.Math上已經存在具有類似功能的Math類（例如： java.lang.Math.abs ），可以使用java.lang.Math.abs自動完成，特別是對於上面的代碼段而言聲明中缺少static （``java.lang.Math.abs`是與之匹配的靜態IDE）