My project's build path in the library has MAVEN Dependences, which has a red fork, which shows that there are two jar packages found, the path shown is the C drive. m2 file, but these two jar packages are special,
Because I put them in the project Web-inf under the LIB, is external dependence, not in the C disk;
Then I use the MAVEN command clean install, or directly clean, all error, is not found a jar file, in the other menu of the Pom file in Eclipse is also indicated that all the jar packages are not dependent on;
-----------------------------Solutions------------------------------
Finally take the stupid method, but it is effective, the Pom file dependencies are taken out, when the Pom file does not have a red fork, and then a one put in, and finally in place Jasperreports.jar dependent pom file again appear red Fork,
Take it out, then experiment with the other, find that there is no problem, and finally determine that the jar package is wrong, also proves that it is not my external dependency file error, so finally the jar is also made an external dependency, and then just fine.
Spent the whole day, change the configuration, even eclipse is deleted, the blood and tears lessons ah ...