1. 用什么插件在java做报表
个人推荐用echarts,这个插件是网络的开源插件，效果相当不错文档完善使用方便，本人目前也在使用，有对应的ECharts - Java类库，ECharts-Java是一个供Java开发使用的ECharts的开发包，主要目的是方便在Java中构造ECharts中可能用到的全部数据结构，如完整的结构 Option。（http://echarts..com/是对应的官网）希望能够帮到您。
2. abap调用java
到底谁调用谁啊？
1.ABAP call Java
REPORT zexecute.
*实例 abap调用java文件
DATA para TYPE string.
PARAMETER mytext TYPE objectname.
PARAMETER mytext1 TYPE objectname.
para = 'Test'. "class name
CONCATENATE para mytext mytext1 INTO para SEPARATED BY space.
CALL METHOD cl_gui_frontend_services=>execute
EXPORTING
application = 'JAVA' "需要执行的语言
parameter = para "参数
default_directory = 'D:\' "路径
minimized = 'X'
synchronous = 'WAIT'
operation = 'OPEN'
EXCEPTIONS
cntl_error = 1
error_no_gui = 2
bad_parameter = 3
file_not_found = 4
path_not_found = 5
file_extension_unknown = 6
error_execute_failed = 7
synchronous_failed = 8
not_supported_by_gui = 9
OTHERS = 10.
*
*
WRITE 'Success'.
2.Java call ABAP
用java来访问SAP的方式不多，一般是JCO，要不就是webservice
要下个JCO.jar包
import com.sap.mw.jco.*;
JCO.Client mConnection = null;
mConnection = JCO.createClient(
"400", // SAP client
"arasoft", // userid
"********", // password
"EN", // language
"host", // application server host name
"00"); // SAP system number
void connect() //Connecting to SAP
void disconnect() //Disconnecting from SAP
void execute(JCO.Function function) //Executing an RFM