我有两张这样的地图:
map1 = new Map<String, MyObject>();
map2 = new Map<String, MyObject>();
MyObject {
Integer mark1;
Integer mark2;
}
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我想要做的是将两个地图合并成map3 <String, MyObject>如下:
map1.place不在map2.place,那么我将条目添加到map3.map2.place不在map1.place,我添加条目map3.map1.place是map2.place,那么我添加此条目:
map1.place, (map1.mark1, map2.mark2)我已经读过了flatMap,但我真的很难用它.有任何线索如何做到这一点?
谢谢!!
我有这个错误: 错误
我检查了我的Eclipse偏好/ Gradle,并且Gradle目录设置得很好.
此外,当我尝试刷新项目时,我的控制台中出现此堆栈错误:
FAILURE: Build failed with an exception.
* Where:
Build file 'C:\java\admin\build.gradle' line: 6
* What went wrong:
A problem occurred evaluating project ':admin'.
> Failed to apply plugin [class 'com.github.jengelman.gradle.plugins.shadow.ShadowJavaPlugin']
> Could not create task of type 'ShadowJar'.
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你知道这里发生了什么吗?
谢谢!
我有一个map<String, Object>和一个数组int[]应该包含地图键.有没有一个很好的简短方法将键转换为int,而不使用循环?
myArray = myMap.keySet().toArray(new int[5]);
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我用Java 8.谢谢!