import vazkii.botania.api.internal.ShaderCallback; //导入依赖的package包/类
/**
 * A callback for the shader, used to pass in uniforms. Return null for no callback.
 * @return a ShaderCallback to use. If getBossBarShaderProgram returns an invalid shader the result of this method is ignored.
 */
public ShaderCallback getBossBarShaderCallback(boolean background, int shader);
 

import vazkii.botania.api.internal.ShaderCallback; //导入依赖的package包/类
/**
 * A callback for the shader, used to pass in uniforms. Return null for no callback.
 */
@SideOnly(Side.CLIENT)
public ShaderCallback getBossBarShaderCallback(boolean background, int shader);