$n$ disjoint balls of capacities $\delta_{1},\dots\delta_{n}$. Let $\{L,E_{1},\cdots,E_{n}\}$ be the standard basis of $H_{2}(X_{n};{\mathbb{Z}})$ consisting of the class of a line $L$, and the classes $E_{i}$, $1\leq i\leq n$, of the exceptional divisors. Using Poincaré duality, the cohomology class of the symplectic form on $X_{n}$ is identified with $\lambda L-\sum_{i}\delta_{i}E_{i}$ while, given any compatible almost-complex structure $J$ on $X_{n}$, the first Chern class $c_{1}:=c_{1}(J)\in H^{2}(X_{n};{\mathbb{Z}})$ is identified with the homology class $K:=3L-\sum_{i} E_{i}$.

The intersection product gives $H_{2}(X_{n};{\mathbb{Z}})$ the structure of an odd unimodular lattice of type $(1,n)$, while $H_{2}(X_{n};{\mathbb{R}})$ becomes an inner product space of signature $(1,n)$. Let ${\mathcal{P}}$ and ${\mathcal{P}}_{+}$ denote, respectively, the positive cone and the forward cone in $H_{2}(X_{n};{\mathbb{R}})$: $${\mathcal{P}}:=
  \left\{ A\in H_{2}(X_{n};{\mathbb{R}})~|~ A\neq 0\text{,~and~} A\cdot A\geq 0 \right\},$$ $${\mathcal{P}}_{+} :=
  \left\{a_{0}L-\sum_{i} a_{i}E_{i}\in{\mathcal{P}}~|~ a_{0}\geq 0 \right\}.$$ Let $\mathcal{C}_{K}\subset H_{2}(X_{n};{\mathbb{R}})$ be the $K$-symplectic cone, that is, $$\mathcal{C}_{K} =
  \{A\in H_{2}(X_{n};{\mathbb{Z}})~|~A=\operatorname{PD}[{\omega}]\text{~for some~}{\omega}\in\Omega_{K}\},$$ where $\Omega_{K}$ is the set of orientation-compatible symplectic forms with $K$ as the symplectic canonical class. Similarly, let ${\mathcal{E}}_{K}\subset H_{2}(X_{n};{\mathbb{Z}})$ be the set of symplectic exceptional homology classes, that is, $${\mathcal{E}}_{K} :=
  \left\{E~|~E\cdot E=-1\text{~and $E$ is represented by some embedded
                          ${\omega}$-symplectic sphere, }{\omega}\in\Omega_{K}\right\}.$$ Building on the work of Taubes on Seiberg-Witten and Gromov invariants, T.-J. Li 